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Ink | Ink is a liquid that is used to write, draw, print, or make marks. The word ink is from Latin and means "colored water". Ink is used in pens, in some computer printers, and in printing presses. In some countries, people write by using ink and brushes. People usually write or print using black ink, but ink can be any color. The first ink was used in Egypt about 2600 BC.
The first inks were carbon inks, made from soot, which is 80% carbon, water and gum arabic. Red ink would need iron oxide (such as haematite) from ground rocks instead of soot. Later, in Europe, people used iron gall ink. This is the kind of ink Johann Sebastian Bach and Leonardo da Vinci used. Now ink colours are produced by man-made dyes.
A disadvantage of many kinds of ink is that they may smudge when wet, spoiling the picture or writing. If water-based ink is used, the writing situation needs to be stable, with the writer seated at a table. Ink in a ballpoint pen (biro) is a kind of gel. It is held in a thin long cylinder (tube) inside the pen. The ink does not fall out of the cylinder as it sticks to the sides of the tube. Therefore ballpoint pens can be used in a wider range of circumstances compared to water-based inks. |
Inch | The inch is a unit of length in the Imperial system and the United States customary system. The abbreviation for inches is in or ". There are 12 inches in a foot. One inch is equal to 2.54 centimetres.
The word "inch" came from Middle English "unche", which came from Old English "ynce", from Latin "uncia" meaning "a twelfth part".
The inch was originally defined as 3 barleycorns. The inch was finally standardised in the International Yard and Pound Treaty in 1959 between the United States, the United Kingdom, South Africa, Australia, New Zealand and Canada. The international yard was made equal to 0.9144 metres. From this, subdivisions and multiples of the yard were specifically defined.
In Britain and the United States, people use inches more than they use millimetres or centimetres. In the rest of the world, international units are almost always used. The inch is not used by scientists.
In the United Kingdom, road signs that show how high a vehicle can be in order to pass through a tunnel are required to be in feet and inches. Theme parks and drive thru signs usually show it in metres. People regularly measure their height in feet and inches. Official medical records, however, are required to record people's height in metric measurements only.
In Canada, a mix of centimetres and inches are used in height. Older generations, especially, use Imperial units. A lot of exposure to Americanized phrases leads to younger generations often having a good understanding of both the Imperial and metric systems.
In the United States, height is always in feet and inches. Science is the only field to use metric measurements.
Other Commonwealth countries, including Ireland, Australia, New Zealand, South Africa and Jamaica use inches to varying degrees. From every day use to exclusively the older community. |
Pint | The pint (abbreviated pt) is a unit of volume in imperial units and United States customary units. There are three types of pints used in different countries. An imperial pint and US pint both equal of a quart and of a gallon.
An imperial fluid ounce is approximately 4% smaller than a US fluid ounce although an imperial pint has 4 more fluid ounces than a US pint, making an imperial pint approximately 20% larger than a US pint.
The imperial pint is the pint used in England, Canada, Ireland, and Burma. The unit may appear in other Commonwealth. Confusion in Canada often arises as liquids are occasionally sold in U.S. pints, near the border, although the official and only pint that is legal in Canada is the imperial pint. The imperial system has no dry pint and volume in dry units, since solid objects are measured by mass. 1 imperial pint equals 568,261.25 mm.
An imperial fluid ounce is approximately 4% smaller than a US fluid ounce although an imperial pint has 4 more fluid ounces than a US pint, making an imperial pint approximately 20% larger than a US pint.
The US wet pint, or more commonly 'pint', is the unit used to measure volume in the United States. It is more common than the dry pint which is used for non-liquid volume measurements. 1 US pint is exactly equal to 473,176.473 mm, defined by the international yard and pound agreement.
The US dry pint was a unit used for measuring the volume of solid objects instead of mass or quantity. |
Italian | The word Italian may mean: |
ISO 19011 | ISO 19011 is the new global accounting standard, replacing accounting standards that were part of ISO 14001 and ISO 9001. It is the most likely basis for accounting reform which could put an end to accounting scandals. |
India | India (Hindi: ), officially the Republic of India (Hindi: ) is a country in South Asia. It is second largest country in population and seventh largest country by land area. It is also the most populous democracy in the world, bounded by the Indian Ocean on the south, the Arabian Sea on the southwest, and the Bay of Bengal on the southeast. It has seven neighbors: Pakistan in north-west, China, Nepal and Bhutan in north, Bangladesh and Myanmar in east and Sri Lanka in south. The Andaman and Nicobar Islands, a union territory of India, is also near Thailand and Indonesia along with Myanmar.
The capital of India is New Delhi. India is a peninsula, bound by the Indian Ocean in the south, the Arabian Sea on the west and Bay of Bengal in the east. The coastline of India is of about long. India has the third largest military force in the world and is also a nuclear weapon state.
India's economy became the world's fastest growing in the G20 developing nations during the last quarter of 2014, replacing the People's Republic of China. India's literacy and wealth are also rising. According to New World Wealth, India is the seventh richest country in the world with a total individual wealth of $5.6 trillion. However, it still has many social and economic issues like poverty and corruption. India is a founding member of the World Trade Organisation (WTO), and has signed the Kyoto Protocol.
India has the fourth largest number of spoken languages per country in the world, only behind Papua New Guinea, Indonesia, and Nigeria. People of many different religions live there, including the five most popular world religions: Hinduism, Buddhism, Sikhism, Islam, and Christianity. The first three religions originated from the Indian subcontinent along with Jainism.
The National emblem of India shows four lions standing back-to-back. The lions symbolise power, pride, confidence, and courage (bravery). Only the government can use this emblem, according to the
The name India comes from the Greek word, "Indus". This came from the word "sindhu", which in time turned into Hind or Hindi or Hindu. The preferred native name or endonym is "Bharat" in Hindi and other Indian languages as contrasted with names from outsiders. Some of the national symbols are:
Two of the main classical languages of the world Tamil language and Sanskrit language were born in India. Both of these languages are more than 3000 years old. The country founded a religion called Hinduism, which most Indians still follow. Later, a king named Chandragupt Maurya built an empire called the Maurya Empire in 300 BC. It made most of South Asia into one whole country. From 180 BC, many other countries invaded India. Even later (100 BC AD 1100), other Indian dynasties (empires) came, including the Chalukyas, Cholas, Pallavas, and Pandyas. Southern India at that time was famous for its science, art, and writing. The Cholas of Thanjavur were pioneers at war in the seas and invaded Malaya, Borneo, Cambodia. The influence of Cholas are still well noticeable in SE Asia.
Many dynasties ruled India around the year 1000. Some of these were the Mughal, Vijayanagara, and the Maratha empires. In the 1600s, European countries invaded India, and the British controlled most of India by 1856.
In the early 1900s, millions of people peacefully started to protest against British control. One of the people who led the freedom movement was Mahatma Gandhi, who only used peaceful tactics, including a way called "ahimsa", which means "non-violence". On 15 August 1947, India peacefully became free and independent from the British Empire. India's constitution was founded on 26 January 1950. Every year, on this day, Indians celebrate Republic Day. The first official leader (Prime Minister) of India was Jawaharlal Nehru.
After 1947, India had a socialist planned economy. It is one of the founding members of the Non-Aligned Movement and the United Nations. It has fought many wars since independence from Britain, including the wars in 1947-48, 1965, 1971, and 1999 with Pakistan and in 1962 with China. It also fought a war to capture Goa, a Portuguese-built port and a city which was not a part of India until 1961. The Portuguese refused to give it to the country, and so India had to use force and the Portuguese were defeated. India has also done nuclear tests in 1974 and 1998, and it is one of the few countries that has nuclear bombs. Since 1991, India has been one of the fastest-growing economies in the world.
India is the largest democracy in the world.
India's government is divided into three parts: the Legislative (the one that makes the laws, the Parliament), the Executive (the government), and the Judiciary (the one that makes sure that the laws are obeyed, the supreme court).
The legislative branch is made up of the Parliament of India, which is in New Delhi, the capital of India. The Parliament of India is divided into two houses: the upper house, Rajya Sabha (Council of States); and the lower house, Lok Sabha (House of People). The Rajya Sabha has 250 members, and the Lok Sabha has 552 members.
The executive branch is made up of the President, Vice President, Prime Minister, and the Council of Ministers. The President of India is elected for a period of five years. The President can choose the Prime Minister, who has most of the power. The Council of Ministers, such as the Minister of Defence, help the Prime Minister. Narendra Modi became the Prime Minister of India on May 16, 2014. He is the 19th Prime Minister of India. The president has less power than the prime minister.
The judicial branch is made up of the courts of India, including the Supreme Court. The Chief Justice of India is the head of the Supreme Court. Supreme Court members have the power to stop a law being passed by Parliament if they think that the law is illegal and contradicts (opposes) the Constitution of India. In India, there are also 24 High Courts.
India is the seventh biggest country in the world. It is the main part of the Indian subcontinent. The countries next to India are Pakistan, Bangladesh, Myanmar, China, Bhutan, and Nepal. It is also near Sri Lanka, an island country.
India is a peninsula, which means that it is surrounded on three sides by water. One of the seven wonders of the world is in Agra: the Taj Mahal. In the west is the Arabian Sea, in the south is the Indian Ocean, and in the east is the Bay of Bengal. The northern part of India has many mountains. The most famous mountain range in India is the Himalayas, which have some of the tallest mountains in the world. There are many rivers in India. The main rivers are the Ganges, the Brahmaputra, the Yamuna, the Godavari, the Kaveri, the Narmada, and the Krishna.
India has different climates. In the South, the climate is mainly tropical, which means it can get very hot in summer and cool in winter. The northern part, though, has a cooler climate, called sub-tropical, and even alpine in mountainous regions. The Himalayas, in the alpine climate region, can get extremely cold. There is very heavy rainfall along the west coast and in the Eastern Himalayan foothills. The west, though, is drier. Because of some of the deserts of India, all of India gets rain for four months of the year. That time is called the monsoon. That is because the deserts attract water-filled winds from the Indian Ocean, which give rain when they come into India. When the monsoon rains come late or not so heavily, droughts (when the land dries out because there is less rain) are possible. Monsoons normally come around July - August.
The Indian Armed Forces is the military of India. It is made up of an Army, Navy and Air Force. There are other parts like Paramilitary and Strategic Nuclear Command.
The President of India is the Commander-in-Chief. However, it is managed by the Ministry of Defence. In 2010, the Indian Armed Forces had 1.32 million active personnel. This makes it one of the largest militaries in the world.
The Indian Army is becoming more modern by buying and making new weapons. It is also building defenses against missiles of other countries. In 2011, India imported more weapons than any other nation in the world.
From its independence in 1947, India fought four wars with Pakistan and a war with China.
For administration purposes, India has been divided into smaller pieces. Most of these pieces are called states, some are called union territories. States and union territories are different in the way they are represented. Most union territories are ruled by administrators sent by the central government. All the states, and the territories of Delhi, and Puducherry elect their local government themselves. In total, there are twenty-eight states, and nine union territories.
States:
Union territories:
There are disputes about certain parts of the Indian borders. Countries do not agree on where the borders are. Pakistan and China do not recognise the disputed territory of Jammu and Kashmir. The Indian government claims it as an Indian state. Similarly, the Republic of India does not recognise the Pakistani and Chinese parts of Kashmir.
In 1914, British India and Tibet agreed on the McMahon Line, as part of the Simla Accord. In July 1914, China withdrew from the agreement. Indians and Tibetans see this line as the official border. China does not agree, and both mainland China and Taiwan do not recognize that Arunachal Pradesh belongs to India. According to them, it is a part of South Tibet, which belongs to China.
The economy of the country is among the world's fastest growing. It is the 7th largest in the world with a nominal GDP of $2,250 billion (USD), and in terms of PPP, the economy is 3rd largest (worth $8.720 trillion USD). The growth rate is 8.25% for fiscal 2010. However, that is still $3678 (considering PPP) per person per year. India's economy is based mainly on:
India's economy is diverse. Major industries include automobiles, cement, chemicals, consumer electronics, food processing, machinery, mining, petroleum, pharmaceuticals, steel, transportation equipment, and textiles.
However, despite economic growth, India continues to suffer from poverty. 27.5% of the population was living in poverty in 2004–2005. In addition, 80.4% of the population live on less than USD $2 a day, which was lowered to 68% by 2009.
There are 1.21 billion people living in India. India is the second largest country by the number of people living in it, with China being the first. Experts think that by the year 2030, India will be the first. About 65% of Indians live in rural areas, or land set aside for farming. The largest cities in India are Mumbai, Kolkata, Delhi, Chennai, Bangalore, Hyderabad, and Ahmedabad. India has 23 official languages. Altogether, 1,625 languages are spoken in India.
There are many different languages and cultures in India. The only geographical place with more different languages and cultures is the African continent. There are two main language families in India, the Indo-Aryan and the Dravidian languages. About 69% of Indians speak an Indo-Arayan language, about 26% speak a Dravidian language. Other languages spoken in India come from the Austro-Asiatic group. Around 5% of the people speak a Tibeto-Burman language.
Hindi is the official language in India with the largest number of speakers. It is the official language of the union. Native speakers of Hindi represent about 41% of the Indian population (2001 Indian census). English is also used, mostly for business and in the administration. It has the status of a 'subsidiary official language'. The constitution also recognises 21 other languages. Either many people speak those languages, or they have been recognised to be very important for Indian culture. The number of dialects in India is as high as 1,652.
In the south of India, many people speak Kannada, Telugu, Tamil and Malayalam. In the north, many people speak Chhattisgarhi, Punjabi, Bengali, Gujarati, and Marathi, Odia, and Bihari.
India has 27 official languages. Its constitution lists the name of the country in each of the languages. Hindi and English (listed in boldface) are the "official languages of the union" (Union meaning the Federal Government in Delhi); Tamil,Sanskrit, Telugu, Kannada, Malayalam, and Odia are officially the "classical languages of India."
Cave paintings from the Stone Age are found across India. They show dances and rituals and suggest there was a prehistoric religion. During the Epic and Puranic periods, the earliest versions of the epic poems "Ramayana" and "Mahabharata" were written from about 500–100 BCE, although these were orally transmitted for centuries before this period. Other South Asian Stone Age sites apart from Pakistan are in modern India, such as the Bhimbetka rock shelters in central Madhya Pradesh and the Kupgal petroglyphs of eastern Karnataka, contain rock art showing religious rites and evidence of possible ritualised music.
Several modern religions are linked to India, namely modern Hinduism, Jainism, Buddhism and Sikhism. All of these religions have different "schools" (ways of thinking) and traditions that are related. As a group they are called the Eastern religions. The Indian religions are similar to one another in many ways: The basic beliefs, the way worship is done and several religious practices are very similar. These similarities mainly come from the fact that these religions have a common history and common origins. They also influenced each other.
The religion of Hinduism is the main faith followed by 79.80% of people in the Republic of India; Islam – 14.23%; Christianity – 2.30%; Sikhism – 1.72%; Buddhism – 0.70% and Jainism – 0.37%.
It's the first time ever since independence that Hindu population percentage fell below 80%.
India sent a spacecraft to Mars for the first time in 2014. That made it the third country and only Asian country to do so, successfully. India is the only country to be successful in its very first attempt to orbit Mars. It was called the Mars Orbiter Mission.
ISRO launched 104 satellites in a single mission to create world record. India became the first nation in the world to have launched over a hundred satellites in one mission. That was more than the 2014 Russian record of 37 satellites in a single launch.
India has the largest movie industry in the world. Indian Tamil movies are poular globally, especially movies of "Super Star" Rajinikanth. Based in Mumbai (formerly Bombay), the industry is also known as Bollywood. It makes 1,000 movies a year, about twice as many as Hollywood. It produces movies almost everyday.
Indians have excelled in Hockey. They have also won eight gold, one silver and two bronze medals at the Olympic games. However, cricket is the most popular sport in India. The Indian cricket team won the 1983 and 2011 Cricket World Cup and the 2007 ICC World Twenty20. They shared the 2002 ICC Champions Trophy with Sri Lanka and won the 2013 ICC Champions Trophy.Cricket in India is controlled by the Board of Control for Cricket in India or BCCI. Domestic tournaments are the Ranji Trophy, the Duleep Trophy, the Deodhar Trophy, the Irani Trophy and the Challenger Series. There is also the Indian cricket league and Indian premier league Twenty20 competitions.
Tennis has become popular due to the victories of the India Davis Cup team. Association football is also a popular sport in northeast India, West Bengal, Goa and Kerala. The Indian national football team has won the South Asian Football Federation Cup many times. Chess, which comes from India, is also becoming popular. This is with the increase in the number of Indian Grandmasters. Traditional sports include kabaddi, kho kho, and gilli-danda, which are played throughout India. |
Insult | An insult is a description of someone that will offend them. It may or may not be true. It is called "derogatory" language. Terms like foolish, stupid, idiot and moron are insults, because they say that a person's mind is not quick or smart.
Insulting someone's mother directly is a serious insult in many cultures.
Ritual insults are part of many cultures. For example, they can be found in sports and military training. They are also very common in jargons. For example, the word "newbie" is a part of net jargon. Calling someone a newbie is usually insulting.
One should be very careful when using new words to describe others.
Usually, someone insults others because they want to feel like they are better or have more power (influence) than the people they insult. They may want this because they are actually afraid that they are worse or less powerful than the people they are insulting.
When someone is insulted, his or her pride is hurt. He or she may want to fight back by insulting the person who insulted him or her. |
Immunology | Immunology is the study of the immune system. The immune system is the parts of the body which work against infection and parasitism by other living things. Immunology deals with the working of the immune system in health and diseases, and with malfunctions of the immune system.
An immune system is present in all plants and animals. We know this because biologists have found genes coding for toll-like receptors in many different metazoans. These toll-like receptors can recognise bacteria as 'foreign', and are the starting-point for immune reactions. The type of immunity which is triggered by the toll-like receptors is called innate immunity. This is because it is entirely inherited in our genome, and is fully working as soon as our tissues and organs are properly developed.
Vertebrates, "and only vertebrates", have a second type of immunity. This is called adaptive immunity, because it 'remembers' previous infections. Then, if the same infection occurs again, the reaction is much stronger and faster. This immunological memory "confers a tremendous survival advantage" and with it vertebrates "can survive over a long lifetime in a pathogen-filled environment".
The innate immune system is usually means all of the cells and systems that does not have to be exposed to a particular pathogen before they can work.
Innate immunity starts with the skin, which is an excellent barrier to infection.
The adaptive immune system includes cells and systems that do require previous exposure to a pathogen. It explains the unique ability of the mammalian immune system to remember previous infections and mount a rapid and robust reaction to secondary infections. This immunological memory is due to the biology of T-cells and B-cells.
Vaccines boost the acquired immune system by offering weak forms of infection that the body can fight off. The system remembers how to do it again when a stronger infection happens. If the vaccine works, the body can then fight off a serious infection.
The distribution of vaccines and other immune system affecting cures can be considered another level of acquired immune system, one governed by access to vaccination and medicine in general. The intersection of this with the spread of disease (as studied in epidemiology) is part of the field of public health.
Errors of the immune system may cause damage. In autoimmune diseases, the body attacks parts of itself because the system mistakes some parts of the body as 'foreign'. Some kinds of arthritis are caused this way.
Sometimes serious pathogens slip in because their surface is disguised as something the host cell walls can accept. That is how viruses work. Once inside a cell, their genetic material controls the cell. Infections like HIV get in this way, and then attack cells which are the basis of the immune system. Artificial means are often used to restore immune system function in an HIV-challenged body, and prevent the onset of AIDS. This is one of the most complex issues in immunology as it involves every level of that system. This research during the 1980s and 1990s radically changed the view of the human immune system and its functions and integration in the human body.
Immunology is a science that examines the structure and function of the immune system. It originates from medicine and early studies on the causes of immunity to disease. The earliest known mention of immunity was during the plague of Athens in 430 BC. Thucydides (460–395 BC) noted that people who had recovered from a previous bout of some diseases could nurse the sick without contracting the illness a second time.
In the 18th century, Pierre-Louis Moreau de Maupertuis made experiments with scorpion venom and observed that certain dogs and mice were immune to this venom. This and other observations of acquired immunity led to Louis Pasteur (1822–1895) developing vaccination and the germ theory of disease. Pasteur's theory was in direct opposition to contemporary theories of disease, such as the miasma theory. It was not until the proofs Robert Koch (1843–1910) published in 1891 (for which he was awarded a Nobel Prize in 1905) that microorganisms were confirmed as the cause of infectious disease. Viruses were confirmed as human pathogens in 1901, when the yellow fever virus was discovered by Walter Reed (1851–1902).
Immunology made a great advance towards the end of the 19th century, through rapid developments, in the study of humoral immunity and cellular immunity. Particularly important was the work of Paul Ehrlich (1854–1915), who proposed the side-chain theory to explain the specificity of the antigen-antibody reaction. The Nobel Prize for 1908 was jointly awarded to Ehrlich and the founder of cellular immunology, Ilya Mechnikov (1845–1916).
The simplest form of immunity is the DNA restriction system in bacteria that prevents infection by bacteriophages. |
Infinity | Infinity is about things that never end.
Sometimes, it is also written formula_1. Infinity means many different things, depending on when it is used. The word is from Latin origin, meaning "without end". Infinity goes on forever, so sometimes space, numbers, and other things are said to be 'infinite', because they never come to a stop.
Infinity is usually not an actual number, but it is sometimes used as one. Infinity often says how "many" there is of something, instead of how "big" something is. For example, there are infinitely many whole numbers (called integers), but there is no integer which is infinitely big. But different kinds of math have different kinds of infinity. So its meaning often changes.
There are two kinds of infinity: potential infinity and actual infinity. Potential infinity is a process that never stops. For example, adding 10 to a number. No matter how many times 10 is added, 10 more can still be added. Actual infinity, on the other hand, refers to objects that are accepted as infinite entities (such as transfinite numbers).
Mathematicians have different sizes of infinity and three different kinds of infinity.
The number of things, beginning with 0, 1, 2, 3, ..., to include infinite cardinal numbers. There are many different cardinal numbers. Infinity can be defined in one of two ways: Infinity is a number so big that a part of it can be of the same size; Infinity is larger than all of the natural numbers. There is a smallest infinite number, "countable infinity". It is the counting number for all of the whole numbers. It is also the counting number of the rational numbers. The mathematical notation is the Hebrew letter aleph with a subscript zero; formula_2. It is spoken "aleph naught".
It was a surprise to learn that there are larger infinite numbers. The number of real numbers, that is, all numbers with decimals, is larger than the number of rational numbers, the number of fractions. This shows that there are real numbers which are not fractions. The smallest infinite number greater than formula_2 is formula_4 (aleph one). The number of mathematical functions is the next infinite cardinal number, formula_5.
And these numbers, called aleph numbers, go on without end.
A different "type" of infinity are the ordinal numbers, beginning "first, second, third, ...". The order "first, second, third, ..." and so on to infinity is "different" from the order "ending" "..., third, second, first". The difference is important for mathematical induction. The simple "first, second, third, ... " has the mathematical name: the Greek letter omega with subscript zero: formula_6. (Or simply omega formula_7.) The infinite series ending "... third, second, first" is formula_8.
The third "type" of infinity has the symbol formula_1. This is treated as addition to the real numbers or the complex numbers. It is the result of division by zero, or to indicate that a series is increasing (or decreasing) without bound. The series 1, 2, 3, ... increases without upper bound. This is written: the limit is formula_10. In calculus, the integral over all real numbers is written: formula_11
Each kind of infinity has different rules.
formula_12 Addition with "alephs" is commutative.
formula_13 Multiplication with "alephs" is commutative.
formula_14
formula_15.
formula_16. Addition with "omegas" is not commutative.
formula_17. Multiplication with "omegas" is not commutative.
formula_18
formula_19
formula_20
formula_21 Otherwise, division by infinity is not meaningful. Subtraction with infinity is not meaningful. |
January | January (Jan.) is the first month of the year in the Julian and Gregorian calendars, coming between December (of the previous year) and February (of the current year). It has 31 days.
January begins on the same day of the week as October in common years, and April and July in leap years. January ends on the same day of the week as February and October in common years, and July in leap years.
January is named for Janus, the Roman god of doors and gates.
January and February were put on the calendar after all the other months. This is because in the original Roman calendar, winter did not have months. Although March was originally the first month, January became the new first month because that was when people chose the new consuls (Roman leaders). The month has 31 days.
January is a winter month in the Northern Hemisphere and a summer month in the Southern Hemisphere. In each hemisphere, it is the seasonal equivalent of July in the other. Perihelion, the point in its orbit where the Earth is closest to the Sun, also occurs in this month, between January 2 and January 5. January begins on the same day of the week as October in common years and on the same day of the week as April and July in leap years. January ends on the same day of the week as February and October in common years and on the same day of the week as July in leap years. January is the only month of the year that always has a "twin" - a month that both begins and ends on the same day of the week as it does. In a common year, this is October, and in a leap year, July.
Every year, January both starts and finishes on the same day of the week as May of the previous year, as each other's first and last days are exactly 35 weeks (245 days) apart.
In common years immediately before other common years, January starts on the same day of the week as April and July of the following year, and in leap years and years immediately before that, September and December of the following year. In common years immediately before other common years, January finishes on the same day of the week as July of the following year, and in leap years and years immediately before that, April and December of the following year.
January's flower is the carnation with its birthstone being the garnet. The meaning of the garnet is constancy.
The first day of January is called New Year's Day. It is said that it became this date when Roman consuls took office on this day in 153 BC. Different calendars across Europe made this the start of the New Year at different times, as some observed it on March 25.
Reaching over from December, the Christmas season in Christianity also extends into this month. Eastern churches celebrate Christmas on January 6 or January 7, and Epiphany on January 18 or January 19 - In Western Christianity this occurs on January 6, with Christmas occurring on December 25.
January 1 is celebrated the Solemnity of Mary, the Mother of God, that is a feast day of precept of the Blessed Virgin Mary. |
June | June is the sixth month of the year, coming between May and July. It has 30 days. In Sweden in 1732 the month had 31 days. June never begins on the same day of the week as any other month, but always ends on the same day of the week as March.
June comes between May and July and is the sixth month of the year in the Gregorian calendar. It is one of four months to have 30 days.
No other month of any year, common or leap year, begins on the same day of the week as June. June ends on the same day of the week as March every year, as each other's last days are 13 weeks (91 days) apart.
In common years, June starts on the same day of the week as September and December of the previous year, and in leap years, April and July of the previous year. In common years, June finishes on the same day of the week as September of the previous year, and in leap years, April and December of the previous year.
Every year, June starts on the same day of the week as February of the following year, as each other's first days are exactly 35 weeks (245 days) apart. In years immediately before common years, June starts on the same day of the week as March and November of the following year, and in years immediately before leap years, August of the following year. In years immediately before common years, June finishes on the same day of the week as August and November of the following year, and in years immediately before leap years, May of the following year.
June is one of two months to have a solstice (the other is December, its seasonal equivalent in both hemispheres), and in this month the Tropic of Cancer in the Northern Hemisphere is turned towards the Sun, meaning that June 20 or June 21 is the Northern Summer Solstice and the Southern Winter Solstice. This means that this date would have the most daylight of any day in the Northern hemisphere, and the least in the Southern Hemisphere. There are 24 hours of daylight at the North Pole and 24 hours of darkness at the South Pole. |
July | July is the seventh month of the year in the Gregorian calendar, coming between June and August. It has 31 days. July was named after Julius Caesar. The mid-way point of the year is either on July 2 or in the night of July 1-2.
July always begins on the same day of the week as April, and additionally, January in leap years. July doesn't end on the same day of the week as any other month in common years, but ends on the same day of the week as January in leap years.
In each hemisphere, it is the seasonal equivalent of January in the other hemisphere. In the North, it is summer and in the South it is winter.
In the Northern Hemisphere, July is often the warmest month of the year, and major sporting events and music festivals are held around this time. In the Southern Hemisphere, it is a winter month, with the coldest-recorded temperature having been measured in Antarctica in this month.
July begins on the same day of the week as April every year and on the same day of the week as January in leap years. No other month in common years ends on the same day of the week as July, but July ends on the same day of the week as January in leap years.
In common years, July starts on the same day of the week as October of the previous year, and in leap years, May of the previous year. In common years, July finishes on the same day of the week as February and October of the previous year, and in leap years, May of the previous year. In common years immediately after other common years, July both starts and finishes on the same day of the week as January of the previous year.
In years immediately before common years, July starts on the same day of the week as September and December of the following year, and in years immediately before leap years, June of the following year. In years immediately before common years, July finishes on the same day of the week as April and December of the following year, and in years immediately before leap years, September of the following year.
July's flower is a variety of the water lily. Its birthstone is the ruby. The meaning for the birthstone ruby is contented mind. Astrological signs for July are Cancer (June 21 - July 21) and Leo (July 22 - August 21).
In the old Roman calendar, July was called "Quintilis", meaning "Fifth Month", because, in the old calendar, the year began in March. Augustus later renamed it July in honor of Julius Caesar, whose birthday was in this month. Augustus later also named the following month, August, after himself. |
Japan | Japan (; Romanised as "nihon" or "nippon") is a country in East Asia. It is a group of many islands close to the east coast of Korea, China and Russia. The Pacific Ocean is to the east of Japan and the Sea of Japan is to the west. Most people in Japan live on one of four of the islands. The biggest of these islands, Honshu, has the most people. Honshu is the 7th largest island in the world. Tokyo is the capital of Japan and its biggest city.
The Japanese people call their country "Nihon" or "Nippon", which means "the origin of the Sun" in Japanese. Japan is a monarchy whose head of state is called the Emperor.
The first people in Japan were the Ainu people and other Jōmon people. They were closer related to Europeans or Arabs. They were later conquered and replaced by the Yayoi people (early Japanese and Ryukyuans). The Yayoi were an ancient ethnic group that migrated to the Japanese archipelago mainly from southeastern China during the Yayoi period (300 BCE–300 CE). Modern Japanese people have primarily Yayoi ancestry at an average of 97%. The indigenous Ryukyuan and Ainu peoples have more Jōmon ancestry on the other hand.
The earliest records on Japan are from Chinese documents. One of those records said there were many small countries (in Japan) which had wars between them and later a country, ruled by a queen, became the strongest, unified others, and brought peace.
The Japanese began to write their own history after the 5th and 6th centuries, when people from Korea and China taught Japan about the Chinese writing system. Japan's neighbours also taught them Buddhism. The Japanese changed Buddhism in many ways. For example, Japanese Buddhists used ideas such as Zen more than other Buddhists.
Japan had some contact with the Europeans in the 16th century. The Portuguese were the first Europeans to visit Japan. Later, the Spanish and Dutch came to Japan to trade. Also, they brought Christianity. Japan's leaders welcomed them at first, but because Europeans had conquered many places in the world, the Japanese were scared they would conquer Japan too. So the Japanese did not let the Europeans come into Japan anymore, except in a small area in Nagasaki city. Many Christians were killed. Only the Chinese, Korean and Dutch people were allowed to visit Japan, in the end, and they were under careful control of the Japanese government. Japan was opened for visitors again in 1854 by Commodore Matthew Perry, when the Americans wanted to use Japanese ports for American whale boats. Perry brought steamships with guns, which scared the Japanese into making an agreement with him.
This new contact with Europeans and Americans changed the Japanese culture. The Meiji Restoration of 1868 stopped some old ways and added many new ones. The Empire of Japan was created, and it became a very powerful nation and tried to invade the countries next to it. It invaded and annexed Ryukyu Kingdom, Taiwan, and Korea. It had wars with China and Russia: the First Sino-Japanese War, the Boxer Rebellion, the Russo-Japanese War, and the Second Sino-Japanese War, which grew to become a part of World War II when Japan became allies with Nazi Germany and Fascist Italy.
In 1941, Japan attacked Pearl Harbor in Hawaii, a water base of the United States, and destroyed or damaged many ships and airplanes. This started the United States' involvement in World War II. American and Japanese forces fought each other in the Pacific. Once airbases were established within range of the Japanese mainland, America began to win, and started dropping bombs on Japanese cities. America was able to bomb most of the important cities and quickly brought Japan close to defeat. To make Japan surrender, the United States dropped two atomic bombs on the cities of Hiroshima and Nagasaki, killing 150,000 Japanese citizens. Soon after this the Soviet Union began to fight against Japan, and the Japanese army in Manchuria lost. Japan surrendered and gave up all the places it took from other countries, accepting the Potsdam Proclamation. The United States occupied Japan and forced it to write a new constitution, in which it promised to never go to war again.
Japan is a group of islands in the Western Pacific, off the coast of China. The four biggest islands are Honshu, Hokkaido, Shikoku, and Kyushu, and there are about 6,000 smaller islands there. Japan is separated from the Asian continent by the Sea of Japan and the East China Sea. Honshu, which means 'Mainland' in the Japanese language, is the biggest island. Hokkaido is the island north of Honshu. Kyushu is the island west of Honshu. Shikoku is the island to the south-west of Honshu.
In the middle of Japan there are mountains. They cover the middle of the islands and leave a very narrow strip of flat land on most coasts. Many of the mountains are extinct volcanoes, but some are still active. The highest of these mountains is the beautiful, volcano-shaped Mt Fuji (3,776 metres or 12,389 feet high). Japan has many earthquakes, in fact there are about 1500 of these every year. The biggest earthquake recorded in Japan was in 2011 - called '2011 Tohoku Earthquake'. It caused great damage to several power plants forcing Japan to shut down all its nuclear plants. There was nuclear core meltdown which caused a serious health risk to nearby villages and cities.
90% of the people living in Japan live in just 10% of the land, near the coast. The other 10% of the people in Japan live away from the coast.
Over 10 cities have more than a million people in them. The biggest city in Japan is Tokyo, which is the capital.
The ruling party is the Liberal Democratic Party (Japan) and the prime minister is Yoshihide Suga. The legislature of Japan is called the National Diet.
In the past, the Japanese learned science by way of China or from Europe in the Meiji Era. However, in recent decades Japan has been a leading innovator in several fields, including chemical engineering, nanotechnology, and robotics. There are many technological companies in Japan, and these companies make products for export.
The robot Asimo was made and introduced in 2000. It was manufactured by Honda.
Many things in Japanese culture originated in China, like Go and bonsai.
Japan's traditional food is seafood, rice, miso soup, and vegetables. Noodles and tofu are also common. Sushi, a Japanese food made of cooked rice with vinegar with other ingredients such as raw fish, is popular around the world.
The religion in Japan is mostly Shinto and Buddhist. Due to the tolerant nature of the two main Japanese religions, and the resulting intermixing of the two, many Japanese identify as both Shinto and Buddhist at the same time. There are small numbers of Christians and Muslims, and a few Jews.
When it comes to popular culture, Japan is famous for making video games. Many of the biggest companies that make games, like Nintendo, Namco, and Sega, are Japanese. Other well-known parts of Japanese arts are comics, called manga, and digital animation, or anime. Many people get to know Japanese or how life in Japan is like by reading manga or watching anime on television.
The Ryukyuans and the Ainu both have their own separate cultures, languages and religion.
The biggest cities in Japan are:
In Japan there are seven traditional regions:
Since Japan is an island nation, Japan has several problems over territory because maritime boundaries can be hard to protect. These days, Japan is competing for at least 4 different territories. It cannot agree with some neighbouring countries on whether the land belongs to Japan or the other country.
There are several important international airports in Japan. Narita is the major international airport in the Tokyo area. Kansai International Airport serves as the main airport for Osaka, Kobe, and Kyoto. Chūbu Centrair International Airport near Nagoya is the newest of the three. Haneda Airport is close to central Tokyo and is the largest domestic airport in the country.
The Shinkansen is one of the fastest trains in the world and connects cities in Honshu and Kyushu. Networks of public and private railways are almost all over the country. People mostly travel between cities in buses.
Modern Japan is divided into 47 prefectures. Before the Meiji period (1868-1912), the nation was divided into provinces which were consolidated in the prefectural system.
Japan has many traditional sports such as sumo, judo, karate, kyudo, aikido, iaido and kendo. Also, there are sports which were imported from the West such as baseball, soccer, rugby, golf and skiing.
Japan has taken part in the Olympic Games since 1912. It hosted the Olympic Games in 1964, 1972 and 1998. From 1912 until now, Japanese sportspeople have won 398 medals in total.
Professional sports are also popular and many sports such as baseball (see Pacific League and Central League), soccer (see List of Japanese football teams), sumo, American football, basketball and volleyball, are played professionally. |
Jargon | Jargon is a special way to use words that are shared only by a certain group of people. They do not mean what the dictionary says they mean. They have different meanings to the people using them than their everyday meaning.
For example, the ordinary words "boot", "net", and "web" also have special meanings for users of computers, the Internet, and the World Wide Web. These, and to flame, to ping and many acronyms are part of net jargon.
An "acronym" means that only some of the letters in the word or phrase are used. Often this is the first letter of each word. Other acronyms found online are simply common shorthand.
Usually, more jargon is created over time.
Jargon is also common in the military. It includes phrases like SNAFU.
Jargon can be used by a clique to prevent others from joining or understanding, but it also is often just used because it is shorter. |
Jupiter | Jupiter is the largest planet in the Solar System. It is the fifth planet from the Sun. Jupiter is a gas giant, both because it is so large and made up of gas. The other gas giants are Saturn, Uranus, and Neptune.
Jupiter has a mass of 1.8986×10 kg. (318 earths). This is more than twice the mass of all the other planets in the Solar System put together.
Jupiter can be seen even without using a telescope. The ancient Romans named the planet after their god Jupiter (Latin: "Iuppiter"). Jupiter is the third brightest object in the night sky. Only the Earth's moon and Venus are brighter.
Jupiter has 79 moons. Of these, around 50 are very small and less than five kilometres wide. The four largest moons of Jupiter are Io, Europa, Ganymede, and Callisto. They are called the Galilean moons, because Galileo Galilei discovered them. Ganymede is the largest moon in the Solar System. It is larger in diameter than Mercury. In 2018 another ten very small moons were discovered
Jupiter is the biggest planet in the Solar System with a diameter of 142,984 km. This is eleven times bigger than the diameter of Earth.
The atmosphere near the surface of Jupiter is about 88 to 92% hydrogen, 8 to 12% helium, and 1% other gases.
The lower atmosphere is so heated and the pressure so high that helium changes to liquid. It rains down onto the planet. Based on spectroscopy, Jupiter seems to be made of the same gases as Saturn. It is different from Neptune or Uranus. These two planets have much less hydrogen and helium gas.
The very high temperatures and pressures in Jupiter's core mean scientists cannot tell what materials would be there. This cannot be found out, because it is not possible to create the same amount of pressure on Earth.
Above the unknown inner core is an outer core. The outer core of Jupiter is thick, liquid hydrogen. The pressure is high enough to make the hydrogen solid, but then it melts because of the heat.
The planet Jupiter is sometimes called a failed star because it is made of the same elements (hydrogen and helium) as is the Sun, but it is not large enough to have the internal pressure and temperature necessary to cause hydrogen to fuse to helium, the energy source that powers the sun and most other stars.
Jupiter is twice as massive as all the other planets in the Solar System put together. It gives off more heat than it gets from the sun.
Jupiter is 11 times the width of Earth and 318 times as massive. The volume of Jupiter is 1,317 times the volume of Earth. In other words, 1,317 Earth-sized objects could fit inside it.
Jupiter has many bands of clouds going horizontally across its surface. The light parts are zones and the darker are belts. The zones and belts often interact with each other. This causes huge storms. Wind speeds of 360 kilometres per hour (km/h) are common on Jupiter. To show the difference the strongest tropical storms on Earth are about 100 km/h.
Most of the clouds on Jupiter are made of ammonia. There may also be clouds of water vapour like clouds on Earth. Spacecrafts such as Voyager 1 have seen lightning on the surface of the planet. Scientists think it was water vapour because lightning needs water vapour. These lightning bolts have been measured as up 1,000 times as powerful as those on Earth.
The brown and orange colours are caused when sunlight passes through or refracts with the many gases in the atmosphere.
One of the biggest features in Jupiter's atmosphere is the Great Red Spot. It is a huge storm which is bigger than the entire Earth. It is on record since at least 1831, and as early as 1665. Images by the Hubble Space Telescope have shown as many as two smaller "red spots" right next to the Great Red Spot. Storms can last for hours or as long as hundreds of years in the case of the Great Red Spot.
Jupiter has a magnetic field like Earth's but 11 times stronger. It also has a "magnetosphere" much bigger and stronger than Earth's. The field traps radiation belts much stronger than Earth's Van Allen radiation belts, strong enough to endanger any spacecraft travelling past or to Jupiter. The magnetic field is probably caused by the large amounts of liquid metallic hydrogen in the core of Jupiter. The four largest moons of Jupiter and many of the smaller ones orbit or go around the planet within the magnetic field. This protects them from the solar wind. Jupiter's magnetic field is so large, it reaches the orbit of Saturn 7.7 million miles (12 million km) away. The Earth's magnetosphere does not even cover its moon, less than a quarter of a million miles (400,000 km) away.
Jupiter also has a thin planetary ring system. These rings are difficult to see and were not discovered until 1979 by NASA's Voyager 1 probe. There are four parts to Jupiter's rings. The closest ring to Jupiter is called the Halo Ring. The next ring is called the Main Ring. It is about wide and only thick. The Main and Halo rings of Jupiter are made of small, dark particles. The third and fourth rings, called the "Gossamer" Rings, are transparent (see through) and are made from microscopic debris and dust. This dust probably comes from small meteors striking the surface of Jupiter's moons. The third ring is called the Amalthea Gossamer Ring, named after moon Amalthea. The outer ring, the Thebe Gossamer Ring, is named after the moon Thebe. The outer edge of this ring is about from Jupiter.
The orbit of a planet is the time and path it takes to go around the Sun. In the amount of time it takes for Jupiter to orbit the Sun one time, the Earth orbits the Sun 11.86 times. One year on Jupiter is equal to 11.86 years on Earth. The average distance between Jupiter and the Sun is 778 million kilometres. This is five times the distance between Earth and the Sun. Jupiter is not tilted on its axis as much as Earth or Mars. This causes it to have no seasons, for example summer or winter. Jupiter rotates, or spins around very quickly. This causes the planet to bulge in the middle. Jupiter is the fastest spinning planet in the Solar System. It completes one rotation or spin in 10 hours. Because of the bulge, the length of the equator of Jupiter is much longer than the length from pole to pole.
Jupiter is the third brightest object in the night sky, after the Moon and Venus. Because of that, people have always been able to see it from Earth. The first person known to really study the planet was Galileo Galilei in 1610. He was the first person to see Jupiter's moons Io, Europa, Ganymede and Callisto. This was because he used a telescope, unlike anyone before him.
No new moons were discovered for more than two hundred years. In 1892, astronomer E.E Barnard found a new moon using his observatory in California. He called the moon Amalthea. It was the last of Jupiter's 67 moons to be discovered by human observation through a telescope.
In 1994, bits of the comet Shoemaker Levy-9 hit Jupiter. It was the first time people saw a collision between two Solar System objects.
Seven spacecraft have flown past Jupiter since 1973. These were Pioneer 10 (1973), Pioneer 11 (1974), Voyagers 1 and 2 (1979), Ulysses (1992 and 2004), Cassini (2000) and New Horizons (2007).
The Pioneer missions were the first spacecraft to take close up pictures of Jupiter and its moons. Five years later, the two Voyager spacecraft discovered over 20 new moons. They captured photo evidence of lightning on the night side of Jupiter.
The Ulysses probe was sent to study the Sun. It only went to Jupiter after it had finished its main mission. Ulysses had no cameras so it took no photographs.
In 2006, the Cassini spacecraft, on its way to Saturn, took some very good, very clear pictures of the planet. Cassini also found a moon and took a picture of it but it was too far away to show the details.
The Galileo mission in 1995 was the first spacecraft to go into orbit around Jupiter. It flew around the planet for seven years and studied the four biggest moons. It launched a probe into the planet to get information about Jupiter's atmosphere. The probe travelled to a depth of about 150 km before it was crushed by the weight of all the gas above it. This is called pressure. The Galileo spacecraft was also crushed in 2003 when NASA steered the craft into the planet. They did this so that the craft could not crash into Europa, a moon which scientists think might have life.
NASA have sent another spacecraft to Jupiter called Juno. It was launched on August 5, 2011 and arrived at Jupiter on July 4, 2016. NASA published some results from the Juno mission in March 2018. Several other missions have been planned to send spacecraft to Jupiter's moons Europa and Callisto. One called JIMO (Jupiter Icy Moons Orbiter) was cancelled in 2006 because it cost too much money.
Jupiter has 79 known moons. The four largest were seen by Galileo with his primitive telescope, and nine more can be seen from Earth with modern telescopes. The rest of the moons have been identified by spacecraft. The smallest moon (S/2003 J 12) is only one kilometre across. The largest, Ganymede, has a diameter of 5,262 kilometres. It is bigger than the planet Mercury. The other three Galilean moons are Io, Europa and Callisto. Because of the way they orbit Jupiter, gravity affects three of these moons greatly. The friction caused by the gravity of Europa and Ganymede pulling on Io makes it the most volcanic object in the Solar System. It has over 400 volcanoes, more than three times as many as Earth.
Jupiter's large gravity has had an effect on the Solar System. Jupiter protects the inner planets from comets by pulling them towards itself. Because of this, Jupiter has the most comet impacts in the Solar System.
Two groups of asteroids, called Trojan asteroids, have settled into Jupiter's orbit round the Sun. One group is called the "Trojans" and the other group is called the "Greeks". They go around the Sun at the same time as Jupiter. |
King | A king is a man who rules a country, because of inheritance. A king usually comes to power when the previous monarch dies, who is usually a family member of his. Sometimes a person may become king due to the previous monarch's abdication, for example George VI. For most of history, most countries were ruled in this way, especially in Europe. Some countries, such as France, are no longer monarchies. Some, such as the United Kingdom, still have a royal family. In some countries, people chose a new king from other people to decide from.
The wife of a king is called a queen. A woman who becomes a ruler because of inheritance is also called a queen.
If a country has a king or a queen, that means it is a monarchy. A country which a king or queen rules is called a kingdom.
In the Muslim world a King would be known as Malik or Sultan. |
Knowledge | Knowledge means the things which are true, as opposed to opinion. Information which is correct is knowledge. Knowledge can always be supported by evidence. If a statement is not supported by evidence, then it is not knowledge. The evidence makes it justified; .
Knowledge can refer to a theoretical or practical understanding of a subject. This was the point of Ryle's distinction between "knowing that" and "knowing how". It can be implicit (as with practical skill or expertise) or explicit (as with the theoretical understanding of a subject); it can be more or less formal or systematic. In philosophy, the study of knowledge is called epistemology. The philosopher Plato defined knowledge as "justified true belief". This definition is the subject of the Gettier problems.
All knowledge is a claim to be true, but the claim can be incorrect. The only claims (propositions) which are certainly true are circular, based on how we use words or terms. We can correctly claim that there are 360 degrees in a circle, since that is part of how circles are defined. The point of Aristotle's syllogism was to show that this kind of reasoning had a machine-like form:
But actually, in the real world, not all swans are white.
The most widely accepted way to find reliable knowledge is the scientific method. Yet one thing all philosophers of science agree is that scientific knowledge is just the best we can do at any one time. All scientific knowledge is provisional, not a claim of absolute truth.
Knowledge in religion is different in that it depends on faith, belief and the authority of religious leaders, not on evidence of a scientific or legal kind. There are differing views on whether religious statements should be regarded as knowledge.
In many expressions of Christianity, such as Catholicism and Anglicanism, knowledge is one of the seven gifts of the Holy Spirit.
In the Garden of Eden knowledge is the factor that made humans greedy and treacherous. But in the Book of Proverbs it states: 'to be wise you must first obey the LORD' (9:10).
In Islam, knowledge has great significance. "The All-Knowing" ("al-ʿAlīm") is one of the Names of God, reflecting distinct properties of God in Islam. The Qur'an asserts that knowledge comes from God () and various "hadith" encourage getting knowledge. Muhammad is reported to have said "Seek knowledge from the cradle to the grave" and "Verily the men of knowledge are the inheritors of the prophets". Islamic scholars, theologians and jurists are often given the title "alim", meaning 'knowledgeable'. |
Kauai | Kauai (Kaua'i in Hawaiian) is the second oldest (after Ni'ihau) and fourth largest of the main Hawaiian Islands, in the United States. Known also as the "Garden Isle", Kaua'i lies 73 miles (117 kilometers) across the Kauai Channel, northwest of Honolulu on Oahu. It is of volcanic origin. The highest point on the island is Kawaikini. It is located above sea level. The wettest spot on Earth, with average rainfall of a year, is just east of Mount Waialeale. The high yearly rainfall has eroded deep valleys and canyons in the central mountain. The waterfalls that have been created by erosion in canyons are now popular tourist spots.
The city of Lihue, on the island's southeast side, is the seat of Kauai County. It has a population of around 6,500, and is the main city on the island. Waimea, which is located on the island's southwest side and the first capital of Kauai, was the first place visited by Englishexplorer Captain James Cook in 1778. It was also the first capital of Kauai. The city is at the head of one of the most beautiful canyons in the world, Waimea Canyon, whose gorge is 900 meters (3,000 feet) deep.
The island of Kauai was featured in Disney's 2002 animated feature film "Lilo & Stitch". |
Kahoolawe | Kahoolawe is the smallest of the eight main volcanic islands of Hawaii. It is west of Maui and south of Lanai. It is roughly 11 miles long by across (). The highest point, Lua Makika, is above sea level. The island is dry because its low elevation does not cause much rain (orographic precipitation) to fall from the northeastern trade winds.
Kahoolawe was used as a gunfire and bombing target by the United States military during World War II. It was a defense training area by the United States Navy from around 1941 until May 1994. Popular opinion in the state against this practice brought the end to this use. Navy has since been trying to cleanup unexploded ordnance (bombs and explosive shells) from the island. Ordnance is still buried or lying on the ground. Other items have washed down gullies and still other unexploded ordnance is underwater offshore. In 1981, the entire island was included on the National Register of Historic Places.
The island is planned to be given back to the Hawaiian people. In 1993, the U.S. Congress passed a law that "recognized the cultural importance of the island, required the Navy to return the island to the State, and directed the Navy to do an unexploded ordnance (UXO) cleanup and environmental restoration" . The turnover officially occurred on November 11, 2003, but the cleanup has not yet been completed. The U.S. Navy was given $400 million and 10 years to complete the large cleanup task, but this work has gone much slower than planned.
In 1993, the Hawaii State Legislature established the Kahoolawe Island Reserve. It is made up of the whole island and waters out to from shore. By State Law, Kahoolawe and its waters can only be used for Native Hawaiian cultural, spiritual, and subsistence purposes; fishing; environmental restoration; historic preservation; and education. Commercial uses are not allowed. The Legislature also created the Kahoolawe Island Reserve Commission (KIRC) to manage the Reserve while it is held in trust for a "future Native Hawaiian Sovereignty entity" .
After the cleanup is finished, the restoration of Kahoolawe will need ways to control erosion, restore the plant life, recharge the water table, and slowly replace alien plants with native ones. Plans will include methods for damming gullies and reducing rainwater runoff. Non-natives will temporarily stabilize some areas before the permanent planting of native plants. |
Killing | Killing a living thing is when someone or something ends that life and makes the living thing die. It means causing a death. When a human being kills another human being, it is called murder or homicide, such as manslaughter.
Pesticides and herbicides are poisons for killing bad wild small animals or plants, respectively.
When a soldier kills another in war, it is called "combat". When the state kills a convict sentenced to capital punishment, it is called execution. When someone kills a powerful person it is called assassination. When a person who wants to die kills himself it is suicide, or euthanasia if killed by another. When people kill other people to eat them, it is called cannibalism. |
Kilometre | The kilometre is a common unit used for longer distances on Earth. The international unit for measuring distances is the metre and a kilometre is 1000 metres. It is used in some countries for measuring road and sea distances. In the UK and the USA, the mile is used more than kilometres for road distances and the nautical mile for sea distances.
It is often used to measure the speed of cars, planes and boats by saying how many kilometres it can travel in an hour. This is shown as km/h.
It is also spelled kilometer. This spelling is used in American English.
One kilometre is 0.6214 miles (3280.84 feet). This means that one mile is 1.6093 kilometres.
One kilometre is the approximate distance a healthy adult human being can walk in ten minutes. |
Language | Language is the normal way humans communicate. Only humans use language, though other animals communicate through other means. The study of language is called linguistics.
Human language has syntax, a set of rules for connecting words together to make statements and questions. Language can also be changed, by adding new words, for example, to describe new things. Other animals may inherit a set of calls which have pee-set functions.
Language may be done by speech or by writing or by moving the hands to make signs. It follows that language is "not" just any way of communicating. Even some human communication is not language: see non-verbal communication. Humans also use language for thinking.
When people use the word "language", they can also mean:
UNESCO says that 2,500 languages are at risk of becoming extinct.
All languages share certain things which separate them from all other kinds of communication.
There are many more things in common between languages.
The capacity to learn and use language is inherited. Normally, all humans are born with this capability. "Which" language is learned by a child depends on which language is spoken by the child's community. The "capacity" is inherited, but the particular language is learned.
Children have a special period, from about 18 months to about four years, which is critical for learning the language. If this is seriously disrupted, then their language skills will be damaged. Older people learn differently, so they seldom learn a second language as well as they learn their native language.
Mathematics and computer science use created languages called formal languages (like computer programming languages), but these may or may not be 'true' languages. Mathematics itself is seen as a language by many. Some people consider musical notation to be a way of writing the musical language.
Chinese is the language with the most native speakers in the world, but Chinese is not really a language. It is a close family of dialects, some of which are as different as Romance languages are from one another.
English is often called "the international language", or lingua franca. It is the main second language of the world and the international language of science, travel, technology, business, diplomacy, and entertainment. French had a similar status until the 20th century, and other languages had it at other times.
Some languages are made up so that a lot of people around the world can learn them, without the new languages being tied to any specific country or place. These are called constructed languages. One of the most popular of these languages is Esperanto, which is sometimes called "La Internacia Lingvo," or "The International Language." Another of these languages is called Volapük, which was popular about a hundred years ago but is much less popular now. It has mostly been replaced by languages like Esperanto, Interlingua, and Ido. Dialects are basically other versions of a language. For example Hoffish is a dialect of swedish.
Part of the reason that Volapük became unpopular is that some sounds are hard to say for people who speak Spanish or English, two of the most widely spoken languages in the world. |
Leisure | Leisure (or free time) is when a person can choose what to do. During a person's leisure time, they do not have an obligation to be at school or work at a job. During leisure time, people can do fun activities, family activities, or other non-work activity, such as hobbies.
Common forms of recreation or leisure are:
A vacation or holiday is the setting aside of time specifically for leisure. During their vacation, some people travel to a different region or country, and stay at a hotel so that they can do things they could not do near home. Other people prefer to spend their vacation time at home in their own community.
In rich industrialized countries such as the US and Canada, as well as in most European countries, workers are allowed to stay home on the weekend (usually Saturday and Sunday), and use it as leisure time. People in poorer developing countries usually have less leisure time, as they have to work longer hours and more days per year. |
Live | Live can be a verb. It rhymes with "give". "To live" means "to be alive" (and not dead). If you live, then you have life.
It can be used in a general way:
Live can be an adjective. It rhymes with "five". |
Life | Life is a concept in biology. It is about the characteristics, state, or mode that separates a living thing from dead matter.
The word itself may refer to a living being or to the processes of which living things are a part. It may refer to the period when a living thing is functional (as between birth and death).
The study of life is called biology: people who study life are called biologists. A lifespan is the average length of life in a species. Most life on Earth is powered by solar energy: the only known exceptions are the chemosynthetic bacteria living around the hydrothermal vents on the ocean floor. All life on Earth is based on the chemistry of carbon compounds, specifically involving long-chain molecules such as proteins and nucleic acid. With water, which all life needs, the long molecules are wrapped inside membranes as cells. This may or may not be true of all possible forms of life in the Universe: it is true of all life on Earth today.
Living things, or organisms, can be explained as open systems. They are always changing, because they exchange materials and information with their environment. They undergo metabolism, maintain homeostasis, possess a capacity to grow, respond to stimuli and reproduce.
Through natural selection, they adapt to their environment in successive generations. More complex living organisms can communicate through various means. Many life forms can be found on Earth. The properties common to these organisms—plants, animals, fungi, protists, archaea, and bacteria—are a carbon and water-based cellular form with complex organization and heritable genetic information.
The systems that make up life have many levels of organization. From smallest to biggest, they are: molecule, cell, tissue (group of cells with a common purpose), organ (part of the body with a purpose), organ system (group of organs that work together), organism, population (group of organisms of the same species), community (all of the organisms that interact in an area), ecosystem (all of the organisms in an area and the non-living surroundings), and biosphere (all parts of the Earth that have life).
At present, the Earth is the only planet humans have detailed information about. The question of whether life exists elsewhere in the Universe is open. There have been a number of claims of life elsewhere in the Universe. None of these have been confirmed so far. The best evidence of life outside of Earth is are nucleic acids that have been found in certain types of meteorites.
One explanation of life is called the cell theory. The cell theory has three basic points: all living things are made up of cells. The cell is the smallest living thing that can do all the things needed for life. All cells must come from pre-existing cells.
Something is often said to be alive if it:
However, not all living things fit every point on this list.
They do, however, fit the biochemical definitions: they are made of the same kind of chemicals.
The thermodynamic definition of life is any system which can keep its entropy levels below maximum (usually through adaptation and mutations).
A modern definition was given by Humberto Maturana and Francisco Varela in 1980, to which they gave the name "autopoiesis":
Roth commented that "In short, organisms are self-reproducing and self-maintaining, or 'autopoietic', systems". This approach makes use of molecular biology ideas and systems science ideas.
Life on Earth is made from organic compounds — molecules that contain carbon. Four types of long-chain molecules (macromolecules) are important: carbohydrates, lipids, proteins, and nucleic acids.
Almost all living things need the chemical elements carbon, hydrogen, oxygen, nitrogen, sulfur, and phosphorus, to build these macromolecules. Living things also need small amounts of other elements, called "trace elements". Water is a very important part of all living things. For example, humans are about two-thirds water. Water is a solvent that lets molecules mix and react with other molecules.
All living things need energy to survive, move, grow, and reproduce. Some can get energy from the environment without help from other living things: these are called producers, or autotrophs. Plants, algae, and some bacteria, a group of producers called photoautotrophs, use the sun's light for energy. When producers use light to make and store organic compounds, this is called photosynthesis. Some other producers, called chemoautotrophs, get energy from chemicals that come out of the ocean floor in hydrothermal vents. Other living things get their energy from organic compounds: these are called consumers, or heterotrophs. Animals, fungi, most bacteria, and most protists are consumers. Consumers can eat other living things or dead material.
Both producers and consumers need to break down organic compounds to free energy. The best way to do this is aerobic respiration, which frees the most energy, but living things can only do aerobic respiration if they have oxygen (O2). They can also break down these compounds without oxygen, using anaerobic respiration or fermentation.
All living things have cells. Every cell has a cell membrane on the outside, and a jelly-like material that fills the inside, called cytoplasm. The membrane is important because it separates the chemicals inside and outside. Some molecules can pass through the membrane, but others cannot. Living cells have genes, made of DNA. Genes say to the cell what to do, like a language. One DNA molecule, with many genes, is called a chromosome. Cells can copy themselves to make two new cells.
There are two main kinds of cells: prokaryotic and eukaryotic. Prokaryotic cells have only a few parts. Their DNA is the shape of a circle, inside the cytoplasm, and they have no membranes inside the cell. Eukaryotic cells are more complex, and they have a cell nucleus. The DNA is inside the nucleus, and a membrane is around the nucleus. Eukaryotic cells also have other parts, called organelles. Some of these other organelles also have membranes.
Taxonomy is how lifeforms are put into groups. The smaller groups are more closely related, but the larger classes are more distantly related. The levels, or ranks, of taxonomy are domain, kingdom, phylum, class, order, family, genus, and species. There are many ideas for the meaning of species. One idea, called the biological species concept, is as follows. A species is a group of living things that can mate with each other, and whose children can make their own children.
Taxonomy aims to group together living things with a common ancestor. This can now be done by comparing their DNA. Originally, it was done by comparing their anatomy.
The three domains of life are Bacteria, Archaea, and Eukarya. Bacteria and archaea are prokaryotic and have only one cell. Bacteria range in size from 0.15 cubic micrometres ("Mycoplasma") to 200,000,000 cubic micrometres ("Thiomargarita namibiensis"). Bacteria have shapes which are useful in classification, such as round, long and thin, and spiral. Some bacteria cause diseases. Bacteria in our intestines are part of our gut flora. They break down some of our food. Both bacteria and archaea may live where larger forms of life cannot. Bacteria have a molecule called peptidoglycan in their cell wall, but archaea do not. Archaea have a molecule called isoprene in their cell membrane, but bacteria do not.
Eukarya are living things with eukaryotic cells, and they can have one cell or many cells. Most eukaryotes use sexual reproduction to make new copies of themselves. In sexual reproduction, two sex cells, one from each parent, join together to make a new living thing.
Plants are eukaryotes that use the Sun's light for energy. They include algae, which live in water, and land plants. All land plants have two forms during their life cycle, called alternation of generations. One form is diploid, where the cells have two copies of their chromosomes, and the other form is haploid, where the cells have one copy of their chromosomes. In land plants, both diploid and haploid forms have many cells. Two kinds of land plants are vascular plants and bryophytes. Vascular plants have long tissues that stretch from end to end of the plant. These tissues carry water and food. Most plants have roots and leaves.
Animals are eukaryotes with many cells, which have no rigid cell walls. All animals are consumers: they survive by eating other organic material. Almost all animals have neurons, a signalling system. They usually have muscles, which make the body move. Many animals have a head and legs. Most animals are either male or female. They need a mate of the opposite sex to make offspring. Sex cells from the male and female can meet inside or outside the body.
Fungi are eukaryotes which may have one cell, like yeasts, or many cells, like mushrooms. They are saprophytes. Fungi break down living or dead material, so they are decomposers. Only fungi, and a few bacteria, can break down lignin and cellulose, two parts of wood. Some fungi are mycorrhiza. They live under ground and give nutrients to plants, like nitrogen and phosphorus. Eukaryotes that are not plants, animals, or fungi are called protists. Most protists live in water.
Over thousands or millions of years, living things can change, through the process of evolution. One kind of evolution is when a species changes over time, such as giraffes growing longer necks. Most of the time, the species because better suited to its environment, a process called adaptation. Evolution can also cause one group of living things to split into two groups. This is called speciation if it makes a new species. An example is mockingbirds on the Galapagos Islands — one species of mockingbird lives on each island, but all the species split from a shared ancestor species. Groups that are bigger than species can also split from a shared ancestor — for example, reptiles and mammals. A group of living things and their shared ancestor is called a clade.
Living things can evolve to be quite different from their ancestors. As a result, parts of the body can also change. The same bone structure became the hands of humans, the hooves of horses, and the wings of birds. Different body parts that evolved from the same thing are called homologous.
Extinction is when all members of a species die. About 99.9% of all species that have ever lived are extinct. Extinction can happen at any time, but it is more common in certain time periods called extinction events. The most recent was 65 million years ago, when the dinosaurs went extinct.
By comparing fossils and DNA, we know that all life on Earth today had a shared ancestor, called the last universal common ancestor (LUCA). Other living things may have been alive at the same time as the LUCA, but they died out. A study from 2018 suggests that the LUCA is about 4.5 billion (4,500,000,000) years old, nearly as old as the Earth. The oldest fossil evidence of life is about 3.5 billion years old.
How did non-living material become alive? This is a difficult question. The first step must have been the creation of organic compounds. In 1953, the Miller–Urey experiment made inorganic compounds into organic compounds, such as amino acids, using heat and energy.
Life needs a source of energy for chemical reactions. On the early Earth, the atmosphere did not have oxygen. Oxidation using the Krebs cycle, which is common today, was not possible. The Krebs cycle may have acted backwards, doing reduction instead of oxidation, and the cycle may have made larger molecules. To make life, molecules needed to make copies of themselves. DNA and RNA make copies of themselves, but only if there is a catalyst — a compound which speeds up the chemical reaction. One guess is that RNA itself served as a catalyst. At some time, the molecules were surrounded by membranes, which made cells. |
Law | Law is a set of rules decided by a particular place or authority meant for the purpose of keeping the peace and security of society.
Courts or police may enforce this system of rules and punish people who break the laws, such as by paying a fine, or other penalty including jail. In ancient societies, laws were written by leaders, to set out rules on how people can live, work and do business with each other. But many times in history when laws have been on a false basis to benefit few at the expense of society, they have resulted in conflict. To prevent this, in most countries today, laws are written and voted on by groups of politicians in a legislature, such as a parliament or congress, elected (chosen) by the governed peoples. Countries today have a constitution for the overall framework of society and make further laws as needed for matters of detail. Members of society generally have enough freedom within all the "legal" things they can choose to do. An activity is "illegal" if it breaks a law or does not follow the laws.
A legal code is a written code of laws that are enforced. This may deal with things like police, courts, or punishments. A lawyer, jurist or attorney is a professional who studies and argues the rules of law. In the United States, there are two kinds of attorneys - "transactional" attorneys who write contracts and "litigators" who go to court. In the United Kingdom, these professionals are called solicitors and barristers respectively.
The "Rule of Law" is the law which says that government can only legally use its power in a way the government and the people agree on. It limits the powers a government has, as agreed in a country's constitution. The "Rule of Law" prevents dictatorship and protects the rights of the people. When leaders enforce the legal code honestly, even on themselves and their friends, this is an example of the rule of law being followed. "The rule of law", wrote the ancient Greek philosopher Aristotle in 350 BC, "is better than the rule of any individual."
Culture is usually a major source of the principles behind many laws, and people also tend to trust the ideas based on family and social habits. In many countries throughout history, religion and religious books like the Vedas, Bible or the Koran have been a major source of law.
Civil law is the legal system used in most countries around the world today. Civil law is based on legislation that is found in constitutions or statutes passed by government. The secondary part of civil law is the legal approaches that are part of custom. In civil law governments, judges do not generally have much power, and most of the laws and legal precedent are created by Members of Parliament.
Common law is based on the decisions made by judges in past court cases. It comes from England and it became part of almost every country that once belonged to the British Empire, except Malta, Scotland, the U.S. state of Louisiana, and the Canadian province of Quebec. It is also the predominant form of law in the United States, where many laws called statutes are written by Congress, but many more legal rules exist from the decisions of the courts. Common law had its beginnings in the Middle Ages, when King John was forced by his barons to sign a document called the Magna Carta.
Religious law is law based on religious beliefs or books. Examples include the Jewish Halakha, Islamic Sharia, and Christian Canon law.
Until the 1700s, Sharia law was the main legal system throughout the Muslim world. In some Muslim countries such as Saudi Arabia and Iran, the whole legal systems still base their law on Sharia law. Islamic law is often criticised because it often has harsh penalties for crimes. A serious criticism is the judgement of the European Court that "sharia is incompatible with the fundamental principles of democracy".
The Turkish Refah Party's sharia-based "plurality of legal systems, grounded on religion" was ruled to contravene the European Convention for the Protection of Human Rights and Fundamental Freedoms. The Court decided Refah's plan would "do away with the State's role as the guarantor of individual rights and freedoms" and "infringe the principle of non-discrimination between individuals as regards their enjoyment of public freedoms, which is one of the fundamental principles of democracy".
The history of law is closely connected to the development of human civilizations. Ancient Egyptian law developed in 3000 BC. In 1760 BC King Hammurabi, took ancient Babylonian law and organized it, and had it chiseled in stone for the public to see in the marketplace. These laws became known as the Code of Hammurabi.
The Torah from the Old Testament is an old body of law. It was written around 1280 BC. It has moral rules such as the Ten Commandments, which tell people what things are not permitted. Sometimes people try to change the law. For example, if prostitution is illegal, they try to make it legal.
In democracies, the people in a country usually choose people called politicians to represent them in a legislature. Examples of legislatures include the Houses of Parliament in London, the Congress in Washington, D.C., the Bundestag in Berlin, the Duma in Moscow and the Assemblée nationale in Paris. Most legislatures have two chambers or houses, a 'lower house' and an 'upper house'. To pass legislation, a majority of Members of Parliament must vote for a bill in each house. The legislature is the branch of government that writes laws, and votes on whether they will be approved.
The judiciary is a group of judges who resolve people's disputes and determine whether people who are charged with crimes are guilty. In some jurisdictions the judge does not find guilt or innocence but instead directs a jury, how to interpret facts from a legal perspective, but the jury determines the facts based on evidence presented to them and finds the guilt or innocences of the charged person. Most countries of common law and civil law systems have a system of appeals courts, up to a supreme authority such as the Supreme Court or the High Court. The highest courts usually have the power to remove laws that are unconstitutional (which go against the constitution).
The executive is the governing center of political authority. In most democratic countries, the executive is elected from people who are in the legislature. This group of elected people is called the cabinet. In France, the US and Russia, the executive branch has a President which exists separately from the legislature.
The executive suggests new laws and deals with other countries. As well, the executive usually controls the military, the police, and the bureaucracy. The executive selects ministers, or secretaries of state to control departments such as the health department or the department of justice.
In many jurisdictions the Head of State does not take part in the day-to-day governance of the jurisdiction and takes a largely ceremonial role. This is the case in many Commonwealth nations where the Head of State, usually a Governor almost exclusively acts "on the advice" of the head of the Executive (e.g. the Prime Minister, First Minister or Premier). The primary legal role of the Head of State in these jurisdictions is to act as a check or balance against the Executive, as the Head of State has the rarely exercised power to dissolve the legislature, call elections and dismiss ministers.
The police enforce the criminal laws by arresting people suspected of breaking the law. Bureaucrats are the government workers and government organizations that do work for the government. Bureaucrats work within a system of rules, and they make their decisions in writing.
Lawyers are people who have learned about laws. Lawyers give people advice about their legal rights and duties and represent people in court. To become a lawyer, a person has to complete a two- or three-year university program at a law school and pass an entrance examination. Lawyers work in law firms, for the government, for companies, or by themselves.
Civil society is the people and groups that are not part of government that try to protect people against human rights abuses and try to protect freedom of speech and other individual rights. Organizations that are part of civil society include political parties, debating clubs, trade unions, human rights organizations, newspapers and charities.
"Corporations are among the organizations that use the legal system to further their goals. Like the others, they use means such as campaign donations and advertising to persuade people that they are right. Corporations also engage in commerce and make new things such as automobiles, vaporisers/e-cigarettes, and Unmanned aerial vehicles (i.e. "drones") that the old laws are not well equipped to deal with. Corporations also makes use of a set of rules and regulations to ensure their employees remain loyal to them (usually presented in a legal contract), and that any disobedience towards these rules are considered uncivilized and therefore given grounds for immediate dismissal. |
L. L. Zamenhof | Ludwik Lejzer Zamenhof (; , ; – ), credited as L. L. Zamenhof and sometimes as the pseudonymous Dr. Esperanto, was an eye doctor, linguist (who creates a language), and scholar who created the international language Esperanto.
Zamenhof was born in 1859 in the town of Białystok, Poland. At the time, Poland was a part of the Russian Empire. Bialystok contained three major groups: Poles, Belorussians, and Yiddish-speaking Jews. Zamenhof thought that one common language would join these groups and stop fights between them.
His first language was said to be Polish. His parents spoke Russian and Yiddish at home. His father was a German teacher, so Zamenhof learned that language from an early age and spoke the language fluently. Later he learned French, Latin, Greek, Hebrew and English. He also had an interest in Italian, Spanish and Lithuanian.
Zamenhof decided that the international language must have a simple grammar and be easier to learn than Volapük, an earlier international language. He attempted to create the international language with a grammar that was rich, and complex. The basics of Esperanto were published in 1887. He translated the Hebrew Bible into Esperanto.
His grandson, Louis-Christophe Zaleski-Zamenhof, was an engineer.
He was 14 times nominated for the Nobel Peace Prize between 1907 and 1917. |
List of countries | This is a list of sovereign states. |
Notes | Provinces and territories of Canada
Canada, a country and sovereign state in the northern part of North America, is made up of thirteen administrative divisions: ten provinces and three territories. The different levels of government in Canada are based on the principles of a federation: those of each of the provinces and territories share power with the federal government. The territories' governments have a more limited set of powers versus the federal government than that of the provinces'.
The provinces are in the south of Canada, near the border with the United States. They go from the Atlantic Ocean in the east to the Pacific Ocean in the west. The territories are to the north, where fewer people live, close to the Arctic Circle and Arctic Ocean.
Here is a list of the provinces and territories, and their standard abbreviations, with their capitals (the cities where their governments are based) and largest cities. Canada's national capital, where the federal government meets, is Ottawa. |
Las Vegas | Las Vegas is a city in the American state of Nevada. There were 640,932 people living in the city in 2015, and more than 2,000,000 people living in the metropolitan area. It is the largest city in Nevada. Las Vegas is also the county seat of Clark County. Carolyn Goodman became the mayor in 2011. Las Vegas and Las Vegans are often stereotypically characterized as fun-loving.
Las Vegas leans to the left. Three of the four congressional districts in Nevada include parts of Las Vegas, and all three congresspeople representing those districts are Democrats from Las Vegas.
Native Americans were the first to reside in the area, specifically the Paiute tribe. It was first called "Las Vegas" (which means "The Meadows" in the Spanish language) by the Spanish. The city is known for its dry weather, as is the rest of southern Nevada. It is surrounded by desert.
The US Army built Fort Baker there in 1864. Las Vegas has natural springs, where people used to stop for water when they were going to Los Angeles or other places in California.
In 1905, 110 acres owned by William A. Clark, on which he built a railroad to Southern California were auctioned and Las Vegas was founded as a railroad town. Las Vegas officially became a city in 1911. |
Lanai | Lanai (or Lānaʻi) is sixth largest of the Hawaiian Islands, in the United States. It is also known as the "Pineapple Island". The island is almost a circle in shape and is 18 miles wide in the longest direction. The land area is 140 sq. miles (367 km). It is separated from the island of Moloka'i by the Kalohi Channel to the north.
Lana'i was first seen by Europeans on 25 February 1779 by Captain Clerke, with "HMS Resolution" on the James Cook Pacific Ocean trip. Clerke took command of the ship after Capt. Cook was killed at Kealakekua Bay on February 14, and was leaving the islands for the North Pacific.
In 1922, Jim Dole, the president of Dole Pineapple Company, bought the island of Lana'i. He made a large part of it into the world's largest pineapple plantation.
Tourism on Lana'i started not long ago. That was when the growing of pineapple was slowly coming to an end in the Islands. On Lana'i, you can be with nature and feel the mood of the Hawaiian countryside. Not like nearby O'ahu, the only town (Lana'i City) is small. It has no traffic or shopping centers. Tourists come mainly to relax.
There are three hotels on Lana'i and several golf courses. |
Leap year | A leap year is a year in which an extra day is added to the Gregorian calendar, which is used by most of the world. A common year (an ordinary year) has 365 days, but a leap year has 366 days. The extra day, February 29, is added to the month of February. In an ordinary year, February has 28 days, but in a leap year it has 29 days. The extra day, called a leap day, is the same day of the week as the first day of the month, February 1. Also, in a leap year, the months of January, April, and July all start on the same day of the week.
A leap year comes once every four years. Because of this, a leap year can always be evenly divided by four. For example, 2020 was a leap year. But a year is a common year if it can be evenly divided by 100 but not by 400. This is why 1600, 2000, and 2400 are leap years, but not 1700, 1800, 1900, 2100, 2200, or 2300.
We have leap years because instead of 365 days, the Earth really takes a few minutes less than 365-1/4 days (365.24219) to go completely around the Sun. Without leap years, the seasons would start one day earlier on the calendar every four years. After 360 years, spring in the Northern Hemisphere and autumn in the Southern Hemisphere would begin on December 21 (which is when winter in the Northern Hemisphere and summer in the Southern Hemisphere presently begins).
A number of countries use a lunar calendar (based on the Moon, instead of the Sun, like our solar calendar is). They have leap years when they add an extra lunar month. Different calendars add the extra month in different ways. So a year which has 366 days instead of 365 days where the month of February has 29 days is called a leap year. |
Leather | Leather is the skin of an animal made into a durable material by tanning. The skins of cows, pigs, and goats are often used to make leather. Skins of snakes, alligators or crocodiles, and ostriches are sometimes used to make fancier leather. Shoes, bags, clothes, and balls are often made of leather. Sometimes people make leather out of whales, ducks, giraffes, and African elephants, but all of these ways of making leather are very simple but can also be very hard and rare sometimes.
The way leather is made is divided into three processes. They are preparing the leather, tanning it, and crusting.
In preparing the leather, many things are done to make it ready for tanning. They include soaking it, removing the hair, liming, deliming, bating, bleaching, and pickling.
Tanning is a process that makes the proteins, especially collagen, in the raw hide stable. It increases the thermal and chemical stability of the animal skins. The difference between fresh and tanned animal skin is that fresh animal skin dries to make it hard and stiff. When water is added to it, it becomes bad. But, animal skin that is tanned dries to make it flexible. It does not become bad when water is added to it.
Crusting is a process that makes the leather thin and lubricates it. Chemicals added when crusting must be set in place. Crusting ends with drying and making the leather soft. It may include splitting, shaving, dyeing, whitening or other methods.
Today, most leather is made from the skin of cattle, which makes up about 65% of all the leather made. Other animals that are used include sheep (about 13%), goats (about 11%), and pigs (about 10%).
Horse skin is used to make strong leather. Lamb and deerskin are used for soft leather. It is used in work gloves and indoor shoes.
Kangaroo leather is used to make things that must be strong and flexible. It is used in bullwhips.
In Thailand, stingray leather is used in wallets and belts. Stingray leather is tough and durable. |
License | A license (or licence) allows someone to do something that they otherwise are not allowed to do. A person usually has to pay some money, and maybe pass a test to get a license. A license is usually written but it does not have to be. Most kinds of licenses can only be used by the person they were given to. Licenses may be temporary or permanent. Some licenses can not be taken away once they are given. A person with a license is called a licensee.
In many countries, if a person tries to do something without the correct license to do it, they might have to pay a fine or go to prison.
There are many different types of licenses.
The laws of most countries say that people are only allowed to drive cars if they have a driver's license. If a person does not have a license, they may have to pay a fine if they are caught by the police. In many countries, a person must take a test and pay money to get a license. The test would check that they know the road rules, and have the skill to drive a car.
Other licenses give permission to shoot animals (often called a hunting license). The hunting license usually says when a person may hunt. A hunter may have to pass a test to show that they understand the rules about hunting.
In the United Kingdom and the Republic of Ireland, if someone has a television set, they must buy a "television licence" every year.
Copyright is a law that gives the owner of a creative work the right to decide what other people can do with it. A person or a company can give a license to a copyright that they own. So in order for another person to use an owner's copyright they need permission from the owner. For example, when someone buys computer software, they also need a license from the creator of the software (a copyright owner) allowing the buyer to use the software.
"License" is a verb and "licence" is a noun. "Licensing sessions" were the meetings of magistrates which decided about giving licences to sell alcohol.
In American English there is no difference in spelling between the verb "to license" meaning to give permission, and the noun "a license" meaning the permission to do something.
A degree in medicine is a qualification showing a person has successfully studied medicine. It is awarded for life. A licence to practice medicine is a legal permission to do so within the territory covered by the licensing authority. The licence may be taken away under certain situations. |
Link | A link, also hyperlink in computing, is a part of a chain. A chain is made of many pieces of metal; each piece is a link.
Today, people also use the word link in a new way. The World Wide Web on the Internet is made of many different Web pages. The computer software that people use to make these pages (HTML) lets us go to other pages in a very fast and easy way.
The person who makes the web page can tell the computer to show a word or a picture on the Web page as a link. This means that when we click on the link with our computer mouse, the computer will show us the new page we want to see. Most links are blue, but they can be any color.
The color of the link will change to dark blue when clicked as the web browser recognises it in the browser's cache. Unless the cache is cleared, the link will always stay dark blue.
There are many ways in making a link on a web page. The process is different for different internet software.
In .htm and .html files, a link can be created using this code:
<nowiki>Text of link</nowiki>
WikiSyntax like MediaWiki uses a simpler way of making links. To create a link to another page of the same website:
<nowiki>Link text</nowiki> or just <nowiki>Page name</nowiki>.
To link to an external website:
<nowiki>Link text</nowiki>, <nowiki></nowiki>, or just <nowiki>http://www.example.com</nowiki>.
BB code is used in forum software. To create a link:
<nowiki>[url]http://www.example.com[/url]</nowiki>, or <nowiki>[url=http://www.example.com]Link text[/url]</nowiki> |
Library | A library is a place where many books are kept. Most libraries are public and let people take the books to use in their home. Most libraries let people borrow books for several weeks. Some belong to institutions, for example, companies, churches, schools, and universities. Also a person's bookshelves at home can have many books and be a library. The people who work in libraries are librarians. Librarians are people who take care of the library.
Other libraries keep famous or rare books. There are a few "Copyright libraries" which have a copy of every book which has been written in that country. Some libraries also have other things that people might like, such as magazines, music on CDs, or computers where people can use the Internet. In school they offer software to learn the alphabet and other details.With the spread of literacy, libraries have become essential tools for learning. Libraries are very important for the progress and development of a society.Libraries are collections of books and other informational materials. People come to libraries for reading, study or reference. Libraries contain a variety of materials. They contain printed materials, films, sound and video recordings, maps, photographs, computer software, online databases, and other media.
A library is not a bookstore (a store that sells books).
The prime purpose of a library is to provide access to knowledge and information. To fulfil this mission, libraries preserve a valuable record of culture. Then they pass down this to the coming generations. Therefore, they are an essential link between the past, present and future.
People use libraries to work. They also use library resources to learn about personal interests. Sometimes, they get recreational media such as films and music. Students use libraries to study.
Libraries help the students to develop good reading and study habits. Public officials use libraries for research and public issues. The libraries provide information and services that are essential for learning and progress.
Many places have a public library, where anybody can join if they live in the area. With a library card, people can borrow books and take them home for several weeks. It does not cost money to get a library card at most public libraries.
Books are kept on shelves in a special order so they are easy to find. Public libraries have lot of books on various topics including story books and many others. Many public libraries have books and CDs about learning English. Stories are kept in alphabetical order by the last name of the person who wrote them, the author. Books about other things are often given a special number, that refers to what they are about. They are then put on the shelf in number order. One number system used by many libraries is the Dewey decimal system.
Many colleges and universities have large academic libraries. These libraries are for the use of college students, professors, and researchers. Academic libraries are used mainly for doing research like studying the solar system or how earthquakes happen. These libraries do not have the same types of books you would find in a public library. They usually do not have fiction books or books for children (unless they are being studied). Academic libraries can have many books, sometimes more than a million.
Special libraries are those libraries that are not public libraries or academic libraries. They are usually small. Many times a special library holds books on a particular subject or even a special kind of book. Some special libraries keep just old books or books by Shakespeare. A special library can be owned by a business for use only by that business. For example, Disney World in Orlando has its own library that is not open to the public but for the use of the people who work for the company.
A librarian is a person who works in a library. Librarians help people find books and information. They can teach people how to find books and use the library. A professional librarian is a person who went to school to study library science. They can earn a degree called a Masters in Library Science.
The earliest known library was discovered in Iraq and belonged to the ancient civilization in Sumer. They didn't use paper books but instead wrote everything on clay tablets using a style of writing called cuneiform. These tablets are over 5,000 years old. The Library of Alexandria, in Egypt, was the largest and most important library of the ancient world. It was destroyed when the Romans conquered Egypt in 30 BC. Rome’s first public library was established by Asinius Pollio who was a lieutenant of Julius Caesar. Eventually Rome would build 28 public libraries within the city. When the Roman Empire fell in 330 AD, many books went east to the city of Byzantium where a large library was built. Other libraries were built in monasteries and public homes.
Libraries began to appear in many Islamic cities, where science and philosophy survived after the fall of the Roman Empire. Christian monks and Islamic libraries exchanged books to copy. |
List of mathematics topics | There are a number of topics in mathematics. Some of them include: |
Like | Like can mean some different things:
1. We can use to like to say that we find a thing is good:
2. We can use like for "the same as" or "nearly the same as":
3. We can also use like for "the same way as":
4. In a question, we can use like to ask people to talk about a thing, or to say if they find it good or not:
5. We can also use like as "for example":
6. In British and American English young people, when talking, have recently started using like as an extra word in the middle of sentences. Sometimes they use it to report what someone said, especially when mimicking the way they said it. This should never be used in writing:
As works in the same way as example 2 - comparing two things using either the word "like" or the word "as" is called making a simile ("As big as an elephant"). It may be better to use the word "as" for this to stop confusion with example 1. |
Political divisions of China | There are twenty-three provinces, four municipalities, five autonomous regions and two special administrative regions in the People's Republic of China. The island of Taiwan is claimed as a province by the People's Republic of China (PRC), but it is not under their control. Taiwan is an island known as Republic of China (Taiwan).
There are 23 provinces in the People's Republic of China.
<nowiki>*</nowiki> The island of Taiwan is claimed as a province by the People's Republic of China (PRC), but it is not under their control. Taiwan is an island known as Republic of China (Taiwan).
There are 4 municipalities in the People's Republic of China. "Municipality" is the common English name for the Chinese "zhíxiáshì", meaning a city directly controlled by the national government.
There are 5 autonomous regions in the People's Republic of China. "Autonomous region" is the common English name for the Chinese "zìzhìqū", meaning an area with greater levels of self-government to accommodate minority groups.
There are 2 special administrative regions in the People's Republic of China. "Special administrative region" is the common English name for the Chinese "tèbié xíngzhèng qū", meaning an area under special administration as a result of treaties that returned former European colonies to Chinese control. |
List of fruits | Fruits on this list are defined as the word is used in everyday speech. It does not include vegetables, whatever their origin.
The following items are fruits, according to the scientific definition, but are sometimes considered to be vegetables: |
Legislature | Legislature is a word that comes from the Latin language, meaning "those who write the laws." A legislature is therefore a group of people who vote for new laws, for example in a state or country.
Each person in the legislature is usually either elected or appointed. The constitution of that state or country usually tells how a legislature is supposed to work.
In many countries, the legislature is called a Parliament, Congress, or National Assembly. Sometimes there are two groups of members in the legislature. This is called a ""bicameral"" legislature. A unicameral legislature has only one group of members.
A country, district, city, or other small area may also have something like a legislature. These are often called councils, and they make smaller laws for their areas. |
Linear algebra | Linear algebra is a branch of mathematics. It came from mathematicians trying to solve systems of linear equations. Vectors and matrices are used to solve these systems. The main objects of study currently are vector spaces and linear mappings between vector spaces. Linear algebra is useful in other branches of mathematics (e.g. differential equations and analytic geometry). It can also be applied to the real world in areas such as engineering, physics and economics.
Linear algebra describes ways to solve and manipulate (rearrange) systems of linear equations.
For example, consider the following equations:
These two equations form a system of linear equations.
It is linear because none of the variables are raised to a power.
The graph of a linear equation in two variables is a straight line.
The solution to this system is:
This is because it makes all of the original equations valid, that is, the value on the left side of the equals sign is exactly the same as the value on the right side for both equations.
Linear algebra uses a system of notation for describing system behavior, called a matrix. For the previous example, the coefficients of the equations can be stored in a coefficient matrix. |
London | London is the capital of the United Kingdom and England. London is the city region with the highest population in the United Kingdom. With it being located along River Thames, London has been a central city since it was founded by the Romans two millennia ago under the name Londinium. London's original city center, the City of London, which in 2011 had 7,375 inhabitants on an area of 2.9 km², is England's smallest city. Since the end of the 19th century, London has also been used for the urban region that has developed around this city center. This area forms the region of London, as well as the Greater London administrative unit, led by the Mayor of London and the London Assembly. In modern times, London is one of the world's most important political, economic and cultural centers. This is not least due to the fact that London was the capital of the British Empire and thus for almost three centuries the center of power for large parts of the globe.
The city itself has around 9.1 million inhabitants (2018), but if you count the entire metropolitan area of London (London Metropolitan Area), you reach around 15 million. The city was considered the largest in the EU by population.
London has a temperate climate with regular, light rain throughout the year. July is the warmest month, with an average temperature at Greenwich of 13.6 ° C to 22.8 ° C. The coldest month is January, with an average of 2.4 ° C to 7.9 ° C. The average annual rainfall is 583.6 mm, and February is normally the driest month. Snow is uncommon in London itself, although there is regular snow in the surrounding area; this is because the extra heat the big city generates makes the city about 5 ° C warmer than surrounding areas in winter.
The Romans built the city of "Londinium" along the River Thames in the year AD 43. The name "Londinium" (and later 'London') came from the Celtic language of the Ancient Britons. In the year AD 61, the city was attacked and destroyed. Then the Romans rebuilt the city, and London became an important trading hub.
After the decline of the Roman Empire, few people remained in London. This was partly because the Anglo-Saxon people of Sub-Roman Britain were primarily agricultural. Once the Romans had gone, trade with Continental Europe dwindled. In the 9th century, more people started living in London again. It became the largest city in England. However, it did not become the capital city of England until the 12th century.
After the railways were built, London grew very big. Greater London has 33 boroughs (neighbourhoods) and a mayor. The old City of London is only a square mile in size but has its own Lord Mayor.
Another famous old part of Greater London is Westminster, which was always a different city from the City of London. In Westminster is Westminster Abbey (a cathedral), The Palace of Westminster (the Houses of Parliament, with Big Ben), and 10 Downing Street (where the Prime Minister lives).
London has an oceanic, or temperate climate. It is not usually very hot or cold. It is often cloudy.
London has many celebrations, festivals and events.
London has five major business districts: the City, Westminster, Canary Wharf, Camden & Islington and Lambeth & Southwark.
The London Stock Exchange is the most international stock exchange and the largest in Europe.
London's largest industry is finance. This includes banks, stock exchanges, investment companies and insurance companies The Bank of England is located in London and is the second oldest bank in the world.
London has many professional services such as law and accounting firms.
The British Broadcasting Company (BBC), which has many radio and TV stations, is in London.
Tourism is one of London's biggest industries. London is the most visited city in the world by international tourists with 18.8 million international visitors per year. Within the UK, London is home to the ten most-visited tourist attractions. Tourism employed about 350,000 full-time workers in London in 2003. Tourists spend about £15 billion per year.
A growing number of technology companies are based in London.
London is a major retail centre, and in 2010 had the highest non-food retail sales of any city in the world, with a total spend of around £64.2 billion. The UK's fashion industry, centred on London, contributes tens of billions to the economy.
For the 19th and much of the 20th centuries London was a major manufacturing centre (see Manufacturing in London), with over 1.5 million industrial workers in 1960. Many products were made in London including ships, electronics and cars. Nowadays, most of these manufacturing companies are closed but some drug companies still make medicine in London.
London has twin and sister city agreements with these cities:
London also has a "partnership" agreement with Tokyo, Japan.
The city has a huge network of transport systems including trains, metros (underground) and five main airports.
The Victorians built many train systems in the mid-19th century (1850s). Their main stations are in London, and the lines go to every part of Great Britain. There were originally five major companies but the five companies became a national rail network in modern times.
There are five airports, though only one is actually in London (London City Airport). There is the London end of the LondonBirmingham canal, which was important to the industrial 19th century. The most used airport is Heathrow International Airport although it is actually outside the city.
The metro or London Underground is a system of electric trains which are in London. It is the oldest underground railway in the world. It started running in 1863 as the "Metropolitan Railway". After the opening the system was copied in many other cities, for example New York and Madrid. Even though it is called "the Underground" about half of it is above the ground. The "Tube" is a slang name for the London Underground, because the tunnels for some of the lines are round tubes running through the ground. The Underground has got 274 stations and over 408 km of track. From 2006–2007 over 1 billion passengers used the underground. |
Litre | A litre (international spelling) or liter (American spelling) is one of the metric units of volume. It is not a basic SI unit, but it is a supplementary unit.
One litre is the volume of 1000 cubic centimetres, that is a cube of 10 × 10 × 10 centimetres (1000 cm). One litre of water at has the mass of exactly one kilogram. This results from the definition given in 1795, where the gram was defined as the weight of one cubic centimetre of melting ice.
The symbol for litre is l or ℓ.
For smaller volumes, the decilitre is used: 10 dl = one litre.
For smaller volumes, the centilitre is used: 100 cl = one litre.
For smaller volumes, the millilitre is used: 1000 ml = one litre.
The capital letter "L" is preferred by some people as the small "l" can look like the number one "1".
The metric system was first introduced in France in 1791. That system did not have its own unit of capacity or volume because volume can be measured in cubic metres. In 1793 work to make the metric system compulsory in France was started by the Temporary Commission of Republican Weights and Measures. Due to public demand, the commission said that the cubic metre was too big for everyday use. They said that a new unit based on the old cadil should be used instead. One cadil was to be 0.001 cubic metres. This was equivalent to a cube with sides 10 cm. The "cadil" was also known as the "pinte" or the "litron". The "pinte" had been an old French unit of measure of capacity. In 1795 the definition was revised. The "cadil" was given the name "litre".
In 1795 the kilogram was defined to be exactly one litre of water at 4 °C. In 1799 the kilogram was redefined. The new definition said that the kilogram was the mass of the "kilogram des archives". In 1901 scientists measured the volume of one litre of water at 4 °C very carefully. They found that it occupied about dm. The BIPM redefined the litre as being "exactly" the volume of one kilogram of water at 4 °C.
In 1960 the SI was introduced. The BIPM changed the definition of the litre back to "one dm". The litre is not part of SI. The BIPM defined the litre as a "Non-SI unit accepted for use with the SI". This was because it is used in many countries. The BIPM said that the litre should not be used for very accurate work.
According to SI rules, the symbol for the litre should be "l". This is because the litre was not named after somebody whose name was "Litre". However the symbol "l" and the number "1" are easily confused. In 1979 the BIPM made an exception for the symbol for the litre. They said that people could use either "L" or "l" as its symbol.
In Europe, milk is sold in one litre cartons. One litre bottle is also a popular package for soft drinks. Most alcoholic drinks are sold as 1/3 litre (0.33 l), ½ litre (0.5 l) or 3/4 litre (0.75 l) bottles. |
Lime | Lime is a green fruit, and the tree fruit itself. They are citrus fruits similar to lemons. Limes are rich in vitamin C. Sailors from Britain were given lemon or lime juice to stop them falling ill with scurvy. This is how they got the nickname "Limey". There are several citrus trees whose fruits are called limes. They include the key lime "Citrus aurantiifolia", the Persian lime, the kaffir lime, and the desert lime "Citrus glauca".
Limes are small, round and bright green. If they stay on the tree for a long time they turn yellow. Then they look like small round lemons.
Lime juice is used in cooking and in drinks. Lime oils are often used in perfumes, used for cleaning, and used for aromatherapy.
Lime tastes acidic and bitter. Lime juice is also made from limes. |
Mathematics | Mathematics is the study of numbers, shapes and patterns. The word comes from the Greek word "μάθημα" (máthema), meaning "science, knowledge, or learning", and is sometimes shortened to maths (in England, Australia, Ireland, and New Zealand) or math (in the United States and Canada). The short words are often used for arithmetic, geometry or simple algebra by students and their schools.
Mathematics includes the study of:
Mathematics is useful for solving problems that occur in the real world, so many people besides mathematicians study and use mathematics. Today, some mathematics is needed in many jobs. People working in business, science, engineering, and construction need some knowledge of mathematics.
Mathematics solves problems by using logic. One of the main tools of logic used by mathematicians is deduction. Deduction is a special way of thinking to discover and prove new truths using old truths. To a mathematician, the reason something is true (called a proof) is just as important as the fact that it is true, and this reason is often found using deduction. Using deduction is what makes mathematics thinking different from other kinds of scientific thinking, which might rely on experiments or on interviews.
Logic and reasoning are used by mathematicians to create general rules, which are an important part of mathematics. These rules leave out information that is not important so that a single rule can cover many situations. By finding general rules, mathematics solves many problems at the same time as these rules can be used on other problems. These rules can be called theorems (if they have been proved) or conjectures (if it is not known if they are true yet). Most mathematicians use non-logical and creative reasoning in order to find a logical proof.
Sometimes, mathematics finds and studies rules or ideas that we don't understand yet. Often in mathematics, ideas and rules are chosen because they are considered simple or neat. On the other hand, sometimes these ideas and rules are found in the real world after they are studied in mathematics; this has happened many times in the past. In general, studying the rules and ideas of mathematics can help us understand the world better. Some examples of math problems are addition, subtraction, multiplication, division, calculus, fractions and decimals. Algebra problems are solved by evaluating certain variables. A calculator answers every math problem in the four basic arithmetic operations.
These theorems have interested mathematicians and people who are not mathematicians.
These are theorems and conjectures that have greatly changed mathematics.
Progress in understanding the nature of mathematics also influences the way mathematicians study their subject.
Mathematics in history, and the history of mathematics.
There is no Nobel prize in mathematics. Mathematicians can receive the Abel prize and the Fields Medal for important works.
The Clay Mathematics Institute has said it will give one million dollars to anyone who solves one of the Millennium Prize Problems.
There are many tools that are used to do mathematics or to find answers to mathematics problems. |
March | March is the third month of the year in the Gregorian calendar, coming between February and April. It has 31 days. March is named after Mars, the Roman god of war.
March always begins on the same day of the week as November, and additionally, February in common years. March always ends on the same day of the week as June.
In ancient Rome, March was called Martius. It was named after the war god (Mars) and the Romans thought that it was a lucky time to begin a war. Before Julius Caesar's calendar reform, March was the first month of the year in the Roman calendar, as the winter was considered to be a monthless period.
March is one of seven months to have 31 days. March begins on the same day of the week as February in common years and November every year, as each other's first days are exactly 4 weeks (28 days) and 35 weeks (245 days) apart respectively. March ends on the same day of the week as June every year, as each other's last days are exactly 13 weeks (91 days) apart.
In common years, March starts on the same day of the week as June of the previous year, and in leap years, September and December of the previous year. In common years, March finishes on the same day of the week as September of the previous year, and in leap years, April and December of the previous year.
In years immediately before common years, March starts on the same day of the week as August of the following year, and in years immediately before leap years, May of the following year. In years immediately before common years, March finishes on the same day of the week as August and November of the following year, and in years immediately before leap years, May of the following year.
In leap years, the day before March 1 is February 29. This determines the position of each day of the year from there on. As an example, March 1 is usually the 60th day of the year, but in a leap year is the 61st day.
In terms of seasons, March is one of two months to have an equinox (the other is September, its seasonal equivalent in both hemispheres), with daylight and darkness of roughly the same number of hours, halfway between the December and June solstices. In the Northern Hemisphere, spring starts in this month, while it is autumn in the Southern Hemisphere.
The official start of either season is March 1, though the equinox can fall on March 20 or 21, occasionally on March 19. The northern spring equinox marks the start of the Iranian New Year and Baha'i New Year. It is from the March 21 date that Easter's date is calculated, on the Sunday after the first full moon in spring, meaning it can fall between March 22 and April 25 in Western Christianity. |
May | May is the fifth month of the year, coming between April and June. It has 31 days. The month of May might have been named for the Roman goddess Maia, or more likely the Roman goddess of fertility Bona Dea, whose festival was held in May.
May never begins or ends on the same day of the week as any other month.
May's flower is the Lily of the Valley. Its birthstone is the emerald. The meaning of the emerald is success in love.
May comes between April and June and is the fifth month of the year in the Gregorian calendar. It is one of seven months to have 31 days. In the older Roman calendar, May was the third month of the year. It is a spring month in the Northern Hemisphere and an autumn month in the Southern Hemisphere. In each hemisphere, it is the seasonal equivalent of November in the other. May is likely to have been named after the Roman goddess Maia, though there is a theory that May might have its name from the Latin "Maiores", meaning "Seniors". The same theory suggests that June would then be named from "Iuniores", meaning "Juniors".
No other month of any year, common or leap year, begins nor ends on the same day of the week as May: this month is the only one that has both of these properties.
In common years, May starts on the same day of the week as August of the previous year, and in leap years, March and November of the previous year. In common years, May finishes on the same day of the week as August and November of the previous year, and in leap years, March and June of the previous year. In leap years and years immediately after that, May starts on the same day of the week as February of the previous year.
Every year, May both starts and finishes on the same day of the week as January of the following year, as each other's first and last days are exactly 35 weeks (245 days) apart. In years immediately before common years, May starts on the same day of the week as October of the following year, and in years immediately before leap years, April and July of the following year. In years immediately before common years, May finishes on the same day of the week as February and October of the following year, and in years immediately before leap years, July of the following year.
In the Northern Hemisphere, May is in late Spring, and May Day on May 1 and Walpurgis Night, during the night of April 30 to May 1, are symbolic of the transition from winter to summer. In the Southern Hemisphere, it is in autumn, and comes just before the Antarctic winter, when emperor penguins breed there.
Special devotions to the Virgin Mary take place in May. |
Music | Music is a form of art that uses sound organised in time. Music is also a form of entertainment that puts sounds together in a way that people like, find interesting or dance to. Most music includes people singing with their voices or playing musical instruments, such as the piano, guitar, drums or violin.
The word "music" comes from the Greek word ("mousike"), which means "(art) of the Muses". In Ancient Greece the Muses included the goddesses of music, poetry, art, and dance. Someone who makes music is known as a musician.
Music is sound that has been organized by using rhythm, melody or harmony. If someone bangs saucepans while cooking, it makes noise. If a person bangs saucepans or pots in a rhythmic way, they are making a simple type of music.
There are four things which music has most of the time:
There is no simple definition of music which covers all cases. It is an art form, and opinions come into play. Music is whatever people think is music. A different approach is to list the qualities music must have, such as, sound which has rhythm, melody, pitch, timbre, etc.
These and other attempts, do not capture all aspects of music, or leave out examples which definitely are music. According to Thomas Clifton, music is "a certain reciprocal relation established between a person, his behavior, and a sounding object". Musical experience and the music, together, are called phenomena, and the activity of describing phenomena is called phenomenology.
Even in the stone age people made music. The first music was probably made trying to imitate sounds and rhythms that occurred naturally. Human music may echo these phenomena using patterns, repetition and tonality. This kind of music is still here today. Shamans sometimes imitate sounds that are heard in nature. It may also serve as entertainment (games), or have practical uses, like attracting animals when hunting.
Some animals also can use music. Songbirds use song to protect their territory, or to attract a mate. Monkeys have been seen beating hollow logs. This may, of course, also serve to defend the territory.
The first musical instrument used by humans was probably the voice. The human voice can make many different kinds of sounds. The larynx (voice box) is like a wind instrument.
The oldest known Neanderthal hyoid bone with the modern human form was found in 1983, indicating that the Neanderthals had language, because the hyoid supports the voice box in the human throat.
Most likely the first rhythm instruments or percussion instruments involved the clapping of hands, stones hit together, or other things that are useful to keep a beat. There are finds of this type that date back to the paleolithic. Some of these are ambiguous, as they can be used either as a tool or a musical instrument.
The oldest flute ever discovered may be the so-called Divje Babe flute, found in the Slovenian cave Divje Babe I in 1995. It is not certain that the object is really a flute. The item in question is a fragment of the femur of a young cave bear, and has been dated to about 43,000 years ago. However, whether it is truly a musical instrument or simply a carnivore-chewed bone is a matter of ongoing debate.
In 2008, archaeologists discovered a bone flute in the Hohle Fels cave near Ulm, Germany. The five-holed flute has a V-shaped mouthpiece and is made from a vulture wing bone. The researchers involved in the discovery officially published their findings in the journal "Nature", in June 2009. The discovery is also the oldest confirmed find of any musical instrument in history. Other flutes were also found in the cave. This flute was found next to the Venus of Hohle Fels and a short distance from the oldest known human carving. When they announced their discovery, the scientists suggested that the "finds demonstrate the presence of a well-established musical tradition at the time when modern humans colonized Europe".
The oldest known wooden pipes were discovered near Greystones, Ireland, in 2004. A wood-lined pit contained a group of six flutes made from yew wood, between 30 and 50 cm long, tapered at one end, but without any finger holes. They may once have been strapped together.
In 1986 several bone flutes were found in Jiahu in Henan Province, China. They date to about 6,000 BC. They have between 5 and 8 holes each and were made from the hollow bones of a bird, the Red-crowned Crane. At the time of the discovery, one was found to be still playable. The bone flute plays both the five- or seven-note scale of Xia Zhi and six-note scale of Qing Shang of the ancient Chinese musical system.
It is not known what the earliest music of the cave people was like. Some architecture, even some paintings, are thousands of years old, but old music could not survive until people learned to write it down. The only way we can guess about early music is by looking at very old paintings that show people playing musical instruments, or by finding them in archaeological digs (digging underground to find old things). The earliest piece of music that was ever written down and that has not been lost was discovered on a tablet written in Hurrian, a language spoken in and around northern Mesopotamia (where Iraq is today), from about 1500 BC. The Oxfords Companion to Music, ed. Percy Scholes, London 1970
Another early piece of written music that has survived was a round called "Sumer Is Icumen In". It was written down by a monk around the year 1250. Much of the music in the Middle Ages (roughly 450-1420) was folk music played by working people who wanted to sing or dance. When people played instruments, they were usually playing for dancers. However, most of the music that was written down was for the Catholic church. This music was written for monks to sing in church. It is called Chant (or Gregorian chant).
In the Renaissance (roughly 1400–1550) there was a lot of music, and many composers wrote music that has survived so that it can be performed, played or sung today. The name for this period (Renaissance) is a French word which means "rebirth". This period was called the "rebirth" because many new types of art and music were reborn during this time.
Some very beautiful music was written for use in church services (sacred music) by the Italian composer Giovanni da Palestrina (1525–1594). In Palestrina's music, many singers sing together (this is called a choir). There was also plenty of music not written for the church, such as happy dance music and romantic love songs. Popular instruments during the Renaissance included the viols (a string instrument played with a bow), lutes (a plucked stringed instrument that is a little like a guitar), and the virginal, a small, quiet keyboard instrument.
In the arts, the Baroque was a Western cultural era, which began near the turn of the 17th century in Rome. It was exemplified by drama and grandeur in sculpture, painting, literature, dance, and music. In music, the term 'Baroque' applies to the final period of dominance of imitative counterpoint, where different voices and instruments echo each other but at different pitches, sometimes inverting the echo, and even reversing thematic material.
The popularity and success of the Baroque style was encouraged by the Roman Catholic Church which had decided at the time of the Council of Trent that the arts should communicate religious themes in direct and emotional involvement. The upper class also saw the dramatic style of Baroque architecture and art as a means of impressing visitors and expressing triumphant power and control. Baroque palaces are built around an entrance of courts, grand staircases and reception rooms of sequentially increasing opulence. In similar profusions of detail, art, music, architecture, and literature inspired each other in the Baroque cultural movement as artists explored what they could create from repeated and varied patterns. Some traits and aspects of Baroque paintings that differentiate this style from others are the abundant amount of details, often bright polychromy, less realistic faces of subjects, and an overall sense of awe, which was one of the goals in Baroque art.
The word baroque probably derives from the ancient Portuguese noun "barroco" which is a pearl that is not round but of unpredictable and elaborate shape. Hence, in informal usage, the word baroque can simply mean that something is "elaborate", with many details, without reference to the Baroque styles of the seventeenth and eighteenth centuries.
In western music, the classical period means music from about 1750 to 1825. It was the time of composers like Joseph Haydn, Wolfgang Amadeus Mozart and Ludwig van Beethoven. Orchestras became bigger, and composers often wrote longer pieces of music called symphonies that had several sections (called movements). Some movements of a symphony were loud and fast; other movements were quiet and sad. The form of a piece of music was very important at this time. Music had to have a nice 'shape'. They often used a structure which was called sonata form.
Another important type of music was the string quartet, which is a piece of music written for two violins, a viola, and a violoncello. Like symphonies, string quartet music had several sections. Haydn, Mozart and Beethoven each wrote many famous string quartets.
The piano was invented during this time. Composers liked the piano, because it could be used to play dynamics (getting louder or getting softer). Other popular instruments included the violin, the violoncello, the flute, the clarinet, and the oboe.
The 19th century is called the Romantic period. Composers were particularly interested in conveying their emotions through music. An important instrument from the Romantic period was the piano. Some composers, such as Frederic Chopin wrote subdued, expressive, quietly emotional piano pieces. Often music described a feeling or told a story using sounds. Other composers, such as Franz Schubert wrote songs for a singer and a piano player called Lied (the German word for "song"). These Lieder (plural of Lied) told stories by using the lyrics (words) of the song and by the imaginative piano accompaniments. Other composers, like Richard Strauss, and Franz Liszt created narratives and told stories using only music, which is called a tone poem. Composers, such as Franz Liszt and Johannes Brahms used the piano to play loud, dramatic, strongly emotional music.
Many composers began writing music for bigger orchestras, with as many as 100 instruments. It was the period of "Nationalism" (the feeling of being proud of one's country) when many composers made music using folksong or melodies from their country. Lots of famous composers lived at this time such as Franz Schubert, Felix Mendelssohn, Frederic Chopin, Johannes Brahms, Pyotr Tchaikovsky and Richard Wagner.
From about 1900 onwards is called the "modern period". Many 20th century composers wanted to compose music that sounded different from the Classical and Romantic music. Modern composers searched for new ideas, such as using new instruments, different forms, different sounds, or different harmonies.
The composer Arnold Schoenberg (1874–1951) wrote pieces which were atonal (meaning that they did not sound as if they were in any clear musical key). Later, Schoenberg invented a new system for writing music called twelve-tone system. Music written with the twelve-tone system sounds strange to some, but is mathematical in nature, often making sense only after careful study. Pure twelve-tone music was popular among academics in the fifties and sixties, but some composers such as Benjamin Britten use it today, when it is necessary to get a certain feel.
One of the most important 20th-century composers, Igor Stravinsky (1882–1971), wrote music with very complicated (difficult) chords (groups of notes that are played together) and rhythms. Some composers thought music was getting too complicated and so they wrote Minimalist pieces which use very simple ideas. In the 1950s and 1960s, composers such as Karlheinz Stockhausen experimented with electronic music, using electronic circuits, amplifiers and loudspeakers. In the 1970s, composers began using electronic synthesizers and musical instruments from rock and roll music, such as the electric guitar. They used these new instruments to make new sounds.
Composers writing in the 1990s and the 2000s, such as John Adams (born 1947) and James MacMillan (born 1959) often use a mixture of all these ideas, but they like to write tonal music with easy tunes as well.
Music can be produced electronically. This is most commonly done by computers, keyboards, electric guitars and disk tables. They can mimic traditional instruments, and also produce very different sounds. 21st-century electronic music is commonly made with computer programs and hardware mixers.
Jazz is a type of music that was invented around 1900 in New Orleans in the south of the USA. There were many black musicians living there who played a style of music called blues music. Blues music was influenced by African music (because the black people in the United States had come to the United States as slaves. They were taken from Africa by force). Blues music was a music that was played by singing, using the harmonica, or the acoustic guitar. Many blues songs had sad lyrics about sad emotions (feelings) or sad experiences, such as losing a job, a family member dying, or having to go to jail (prison).
Jazz music mixed together blues music with European music. Some black composers such as Scott Joplin were writing music called ragtime, which had a very different rhythm from standard European music, but used notes that were similar to some European music. Ragtime was a big influence on early jazz, called Dixieland jazz. Jazz musicians used instruments such as the trumpet, saxophone, and clarinet were used for the tunes (melodies), drums for percussion and plucked double bass, piano, banjo and guitar for the background rhythm (rhythmic section). Jazz is usually improvised: the players make up (invent) the music as they play. Even though jazz musicians are making up the music, jazz music still has rules; the musicians play a series of chords (groups of notes) in order.
Jazz music has a swinging rhythm. The word "swing" is hard to explain. For a rhythm to be a "swinging rhythm" it has to feel natural and relaxed. Swing rhythm is not even like a march. There is a long-short feel instead of a same-same feel. A "swinging rhythm" also gets the people who are listening excited, because they like the sound of it. Some people say that a "swinging rhythm" happens when all the jazz musicians start to feel the same pulse and energy from the song. If a jazz band plays very well together, people will say "that is a swinging jazz band" or "that band really swings well."
Jazz influenced other types of music like the Western art music from the 1920s and 1930s. Art music composers such as George Gershwin wrote music that was influenced by jazz. Jazz music influenced pop music songs. In the 1930s and 1940s, many pop music songs began using chords or melodies from jazz songs. One of the best known jazz musicians was Louis Armstrong (1900–1971).
"Pop" music is a type of "popular" music that many people like to listen to. The term "pop music" can be used for all kinds of music that was written to be popular. The word "pop music" was used from about 1880 onwards, when a type of music called music was popular.
Modern pop music grew out of 1950's rock and roll, (for example Chuck Berry, Bo Diddley and Little Richard) and rockabilly (for example Elvis Presley and Buddy Holly). In the 1960s, The Beatles became a famous pop music group. In the 1970s, other styles of music were mixed with pop music, such as funk and soul music. Pop music generally has a heavy (strong) beat, so that it is good for dancing. Pop singers normally sing with microphones that are plugged into an amplifier and a loudspeaker.
"Musical notation" is the way music is written down. Music needs to be written down in order to be saved and remembered for future performances. In this way composers (people who write music) can tell others how to play the musical piece as it was meant to be played.
Solfège (sometimes called solfa) is the way tones are named. It was made in order to give a name to the several tones and pitches. For example, the eight basic notes "Do, Re, Mi, Fa, So, La, Ti, Do" are just the names of the eight notes that confirm the major scale.
Music can be written in several ways. When it is written on a staff (like in the example shown), the pitches (tones) and their duration are represented by symbols called notes. Notes are put on the lines and in the spaces between the lines. Each position says which tone must be played. The higher the note is on the staff, the higher the pitch of the tone. The lower the notes are, the lower the pitch. The duration of the notes (how long they are played for) is shown by making the note "heads" black or white, and by giving them stems and flags.
Music can also be written with letters, naming them as in the solfa "Do, Re, Mi, Fa, So, La, Ti, Do" or representing them by letters. The next table shows how each note of the solfa is represented in the Standard Notation:
The Standard Notation was made to simplify the lecture of music notes, although it is mostly used to represent chords and the names of the music scales.
These ways to represent music ease the way a person reads music. There are more ways to write and represent music, but they are less known and may be more complicated.
People can enjoy music by listening to it. They can go to concerts to hear musicians perform. Classical music is usually performed in concert halls, but sometimes huge festivals are organized in which it is performed outside, in a field or stadium, like pop festivals. People can listen to music on CD's, Computers, iPods, television, the radio, casette/record-players and even mobile phones.
There is so much music today, in elevators, shopping malls, and stores, that it often becomes a background sound that we do not really hear.
People can learn to play an instrument. Probably the most common for complete beginners is the piano or keyboard, the guitar, or the recorder (which is certainly the cheapest to buy). After they have learnt to play scales, play simple tunes and read the simplest musical notation, then they can think about which instrument for further development. They should choose an instrument that is practical for their size. For example, a very short child cannot play a full size double bass, because the double bass is over five feet high. People should choose an instrument that they enjoy playing, because playing regularly is the only way to get better. Finally, it helps to have a good teacher.
Anyone can make up his or her own pieces of music. It is not difficult to compose simple songs or melodies (tunes). It's easier for people who can play an instrument themselves. All it takes is experimenting with the sounds that an instrument makes. Someone can make up a piece that tells a story, or just find a nice tune and think about ways it can be changed each time it is repeated. The instrument might be someone's own voice.
The fact is, there are tons of instruments in the world. |
Madrid | Madrid (pronounced: “mah-DRID” or /məˈdrɪd/) is the capital and largest city of Spain. Madrid is in the middle of Spain, in the Community of Madrid. The Community is a large area that includes the city as well as small towns and villages outside the city. 7 million people live in the Community. More than 3 million live in the city itself. It is the largest city of Spain and, at 655 m (2,100 ft) above sea level, the second highest capital in Europe (after the Andorran capital Andorra la Vella). It is the third largest city in the European Union. As it is the capital city, Madrid is where the monarch lives and also where the government meets. Madrid is the financial centre of Spain. Many large businesses have their main offices there. It has four important footballs teams, Real Madrid, Atlético Madrid, Getafe, and Rayo Vallecano. People who live in Madrid are called madrileños.
Madrid was ruled by the Romans from the 2nd century. After AD 711 it was occupied by the Moors. In 1083 Spain was ruled again by Spaniards. Catholic kings ruled the country. By the mid-16th century it had become the capital of a very large empire. Spain was ruled by monarchs from the House of Habsburg, then the House of Bourbon. After the Spanish Civil War it was ruled by a dictator until the mid-1970s when it became a democracy.
Although it is a modern city, a lot of its history can be seen and felt as one walks along the streets and in the large squares of the city. There are beautiful parks, famous buildings, art galleries and concert halls.
During the history of Spain many different people have lived there. The Phoenicians came in 1100 BC, followed by Carthaginians, Romans, Vandals, Visigoths and Moors. It was not until 1492, when the Catholic Monarchs got power, that Spain became a united country. Jews and Moors, who had lived happily there for many years, were driven away. Spain became very rich because it conquered many overseas countries, especially in Central and South America. However, Spain fought many wars and lost much of its treasure. It was very poor in 1936 when the Civil War was fought. General Franco became a harsh dictator until 1975 when Juan Carlos I was brought back to Spain and made king. There is now a democratic government.
In prehistoric times people lived in the area which is now Madrid. The Romans lived there for several centuries. The origin of today’s city really starts in the 9th century when Muhammad I had a small palace built where the Palacio Real stands today. The Moors built strong forts in Madrid in 865 and put a wall round the city. These walls stood until 1476 when they were knocked down. In 1561 Felipe I moved the royal court from Toledo to Madrid. Madrid had now become the capital of a very large empire. Over the next years and decades the Plaza Mayor was built and many great buildings and monuments, many of which still stand.
When Ferdinand II of Aragon and Queen Isabella of Castile came to Madrid, Spain had become a very rich country. The 16th and 17th centuries are now known as the “Golden Century”. Their grandson was the famous Charles I of Spain (also known as Charles V, Holy Roman Emperor). He liked his court to be in Seville. His son, Philip II (1527–1598) moved the court to Madrid in 1561.
In the late 1800s there was a revolt, known as the First Spanish Republic. Later the monarchy was restored, but then there was a Second Spanish Republic followed by the Spanish Civil War. The Second Spanish Republic started on 14 April 1931 and was celebrated in La puerta del Sol which is the center of the city. Madrid suffered a lot in this war. It was bombed by airplanes.
During the dictatorship of Francisco Franco, especially during the 1960s, south Madrid became very industrialized, and many people from the rural areas moved to Madrid especially to the south east of the city.
When General Franco died and democracy was restored, Madrid became more prosperous. During the 1980s and 1990s many new buildings were put up.
Madrid has been attacked many times by terrorists. This includes the bombing of a restaurant in 1985, killing 18 people and the of trains in 2004, killing over 190 people.
Madrid has a hot-summer Mediterranean climate ("Csa" in the Köppen climate classification). Most rain falls in autumn and spring. The winters are cool because it is high up, and occasionally it snows. The summers are hot and dry. Often the temperature is above 30 °C (86 °F) in July and can often reach 40 °C (104 °F). At night it is much cooler. This is why people have a sleep (siesta) in the afternoon when it is hot. Then they come out again in late afternoon and often eat dinner late at night.
Spain's Royal Palace is in Madrid. It is one of the largest palaces in all of Western Europe. But the king and his family do not live there anymore; they live in a smaller palace, and only use the Royal Palace for important events, like meeting other kings and other official ceremonies. One can go inside the Royal Palace and learn about the history of Spanish monarchy.
Other famous buildings are: The Prado Museum, the Temple of Debod, the Santiago Bernabeú Stadium and the Cuatro Torres Business Area.
There are a lot of very big and important art museums in Madrid. The most famous ones are the Prado Museum, the Queen Sofia Museum, and the Thyssen-Bornemisza museum. These show off paintings, sculptures, and other works of art from some of the most famous artists in the world.
Many famous, important, and valuable works of art are in these museums. For example, the Queen Sofia museum has a famous painting by Pablo Picasso, called "Guernica". Picasso painted this painting to show how sad and angry it made him when the German Nazis destroyed a town in Spain called Guernica in 1937. Picasso had said that the painting should never return to Spain until it was a democracy again. Once that happened, they built the Queen Sofia museum just to have a good place to put it.
There are many other sights to see in Madrid. Many people go to see the Plaza Mayor which was a market place. The Plaza de la Villa was another famous market place. There are a lot of shops along the Gran Via. Real Madrid football fans celebrate at the Plaza de Cibeles. Two famous gates to see are the Puerta del Sol and the Puerta de Alcalá. A more recent landmark is the Almudena Cathedral.
Madrid has some lovely parks. The Retiro Park is the most famous. The Cristal Palace can be found in this park.
The Plaza de Toros is visited by many tourists. Bullfights take place there. |
Montreal | Montreal (, spelled "Montréal" in French) is a city in the country of Canada. It is the largest city in the province of Quebec and the second-largest city in Canada. It is the second-largest French-speaking city in the world after Paris.
Montreal is built on an island sitting in the Saint Lawrence River. More than three million people live in the Montreal region. At the centre of Montreal is a mountain called Mount Royal. The suburb of Westmount, is a very affluent suburb of Quebec.
Most of the people who live in Montreal speak French, but English is also commonly spoken, as a second language.
The name 'Montréal' comes from "Mont Royal", which means 'Royal Mountain' in French. It was originally called "Ville-Marie", or City of Mary.
Montreal has always played a very important part in the history and development of Canada. It continues to be a large Canadian industrial and commercial centre, as well as a major seaport (via the Saint Lawrence River). It once was the largest city in Canada, before Toronto grew to be larger.
Tourists visit Montreal for its historical and cultural interest. One can visit the Old City in horse-drawn carriages, where many buildings from the earliest years stand and remind of the way of life that started in the New World, when Montreal was just a fur trading outpost belonging to France over 350 years ago.
Montreal is in the southwest of Quebec, 530 kilometres north of New York City. The city itself is located on an island, the Island of Montreal. Near the downtown area, there is a hill called "Mount Royal" ("Mont Royal" in French).
Montreal's economy is the second largest in Canada. The city's port is the biggest inland port (a port that is not on the sea) in the world. Many large corporations have their main offices in Montreal. It also hosts many international organizations like ICAO, the World Anti-Doping Agency, and IATA. The city is home to four major Universities, welcoming students from all parts of Canada and from all over the world.
Montreal is also known for its cultural production sector. Because the city has many different buildings, movies are easy to film there. The circus troupe (group) "Cirque du Soleil" is from Montreal. The city is also known for its festivals, like the Montreal Jazz Festival and "Just For Laughs".
Some video game companies also have studios in Montreal.
Montreal is the cultural capital of Quebec and French-speaking Canada.
Montreal has many beautiful churches (Montreal is referred to locally as 'the city of a hundred churches'), including the largest church in Canada, and also many important art, history, and science museums. You can also visit the location of the 1967 World's Fair, where today, as well as many other attractions, one will find the Circuit Gilles Villeneuve Formula One automobile race course. Also of interest is the site where the 1976 Summer Olympic Games were held, and the modern architecture of the Olympic stadium (the 'Big O') and its tall inclined observation tower (the highest inclined tower in the world); now a landmark of Montreal.
A lot of Montrealers are interested in hockey, and Montreal is home to its own ice hockey team called the Montreal Canadiens who play in the National Hockey League (NHL). |
Macadamia nut | The macadamia nut is the fruit of a tree that first came from the east coast of Australia. There is
more than one kind of Macadamia tree. Only one kind is grown for food.
The tree is an evergreen (stays green all year long). It grows up to high. It has groups of small white flowers. It grows best in subtropical (wet and always warm) climates. It needs well-drained soil (water can flow away easily) and of rain a year.
The nutmeat (the soft part inside the shell that can be eaten) is mostly a creamy white color. Sometimes it looks a bit yellow. It has a flavor that many people like. Macadamias are eaten roasted (cooked) by themselves. They are used in cookies, cakes, pastries, and candies. People use them like almonds and cashews as part of cooked meals. This is an Oriental style of cooking.
The first commercial orchard was started in Australia in the late 1880s. Commercial production started in Hawaii during the 1920s. Production later spread to California, Mexico, and other places with warm climate.
Macadamias are poisonous to dogs. A dog usually needs 24 to 48 hours to recover fully after eating macadamias.The plant is in the Proteaceae family of flowering plants. |
Maui | Maui is the second largest of the Hawaiian Islands, in the United States.
It has a population of just over 100,000 and is 727 square miles (1883 km²) in size. Maui is part of Maui County, Hawaii. The larger (or better known) towns include Kahului, Wailuku, Lahaina, Hana, and Wailea. Main industries are agriculture and tourism.
Maui was named for the demi-god Maui. In Hawaiian legend, he raised all the islands from the sea. Maui is also known as the "Valley Isle" for the large fertile isthmus (narrow land connection) between two volcanoes.
Maui is a volcanic doublet: an island formed from two volcanic mountains that are joined together. The older volcano, Mauna Kahalawai, is much older and has been very worn down. In common talk it is called the West Maui Mountain. The larger volcano, Haleakala, rises above 10,000 feet (3,050 m). The last eruption of Haleakala happened over 200 years ago, and this lava flow can be seen between Ahihi Bay and La Perouse Bay on the southeast shore.
Other places on Maui popular with visitors include:
Golf courses on Maui include: |
Molokai | Molokai (sometimes mistakenly called Molokaʻi) is the fifth largest island in the U.S. Hawaiian Islands. The island is 38 miles long and 10 miles across. Its land area is 261 square miles. The highest mountain is named Kamakou, and it is 4,970 feet (1,514 meters) high.
Molokai has many local indigenous names including Molokai 'Aina Momona (land of abundance), Molokai Pule O'o (land of powerful prayer), and Molokai Nui A Hina (of the goddess Hina). It is one of the least developed of the Hawaiian islands.
The only big town is named Kaunakakai, which is also the main or chief port on the island. The airport is in Central Molokai. Also on the island is Kalaupapa, which is a place for people who have a diease called leprosy.
Molokai has many Hawaiian fish ponds along its south shore. Many of these have been cleaned and fixed. |
Money | Money, also sometimes called Currency, can be defined as anything that people use to buy goods and services. Money is what many people receive for selling their own things or services.
There are lots of different kinds of money in the world. Most countries have their own kind of money, such as the United States dollar or the British pound.
money is also called many other names, like currency or cash.
The idea of bartering things is very old. A long time ago, people did not buy or sell with money. Instead, they traded one thing for another to get what they wanted or needed. One person who owned many cows could trade with another person who had a lot of wheat. Each would trade a little of what he had with the other. This would support the people on his farm. Other things that were easier to carry around than cows also came to be held as valuable. This gave rise to trade items such as jewelry and spices.
When people changed from trading in things like, for example, cows and wheat to using money instead, they needed things that would last a long time. They must still have a known value, and could be carried around. The first country in the world to make metal coins was called Lydia. These first appeared during the 7th century BC, in the western part of what is now Turkey. The Lydian coins were made of a weighed amount of precious metal and were stamped with a picture of a lion. This idea soon spread to Greece, the rest of the Mediterranean, and the rest of the world. Coins were all made to the same size and shape. In some parts of the world, different things have been used as money, like clam shells or blocks of salt.
Besides being easier to carry than cows, using money had many other advantages. Money is "easier to divide" than many trade goods. If someone own cows, and wants to trade for only "half a cow's worth" of wheat, he probably does not want to cut his cow in half. But if he sells his cow for money, and buys wheat with money, he can get exactly the amount he wants.
Cows die, and wheat rots. But money "lasts longer" than most trade goods. If someone sells a cow for money, he can save that money away until he needs it. He can always leave it to his children when he dies. It can last a very long time, and he can use it at any time.
Not every cow is as good as another cow. Some cows are sick and old, and others are healthy and young. Some wheat is good and other wheat is moldy or stale. So if a person trades cows for wheat, he might have a hard time arguing over how much wheat each cow is worth. However, money is "standard". That means one dollar is worth the same as another dollar. It is easier to add up and count money, than to add up the value of different cows or amounts of wheat.
Later, after coins had been used for hundreds of years, paper money started out as a promise to pay in coin, much like an "I.O.U." note. The first true paper money was used in China in the 10th century AD. Paper money was also printed in Sweden between 1660 and 1664. Both times, it did not work well, and had to be stopped because the banks kept running out of coins to pay on the notes. Massachusetts Bay Colony printed paper money in the 1690s. This time, the use became more common.
Today, most of what people think of as money is not even things you can hold. It is numbers in bank accounts, saved in computer memories. Many people still feel more comfortable using coins and paper, and do not totally trust using electronic money on a computer memory.
Many types of money have been used at different times in history. These are:
"Commodity money" can be used for other purposes besides serving as a medium of exchange. We say it possesses intrinsic value, because it is useful or valuable by itself. Some examples of commodity money are cattle, silk, gold and silver. Convertible paper money is money that is convertible into gold and silver. Gold and Silver certificates are convertible paper money as they can be fully convertible into gold and silver.
Inconvertible money is money that cannot be converted into gold and silver. Notes and coins are inconvertible money. They are inconvertible and are declared by the government money. Such fiat money is a country's legal tender. Today, notes and coins are the currencies used in bank deposits.
Types of bank deposits: |
Multiplication | Multiplication is an arithmetic operation for finding the "product" of two numbers in mathematics. It is often represented by symbols such as formula_1 and formula_2. Multiplication is the third operation in math, after addition which is the first, and subtraction which is the second. It can also be defined on non-number mathematical objects as well.
With natural numbers, multiplication gives the number of tiles in a rectangle, where one of the two numbers equals the number of tiles on one side, and the other number equals the number of tiles on the other side.
With real numbers, multiplication gives the area of a rectangle where the first number is the same as the size of one side, and the second number is the same as the size of the other side.
For example, three multiplied by five is the total of five threes added together, or the total of three fives. This can be written as 3 × 5 = 15, or spoken as "three times five equals fifteen." Mathematicians refer to the two numbers to be multiplied as "coefficients", or ""multiplicand"" and ""multiplicator"" separately (where Multiplicand × multiplicator = product).
Multiplication between numbers is said to be commutative—when the order of the numbers does not influence the value of the product. This is true for the integers (whole numbers), e.g. 4 × 6 is the same as 6 × 4, and also for the rational numbers (fractions), and for all the other real numbers (representable as a field in the continuous line), and also for complex numbers (numbers representable as a field in the plane). However, it is not true for quaternions (numbers representable as a ring in the four-dimensional space), vectors or matrices.
The definition of multiplication as repeated addition provides a way to arrive at a set-theoretic interpretation of multiplication of cardinal numbers. A more accurate representation is to think of it as scaling quantities. This animation illustrates 3 being multiplied by 2, giving 6 as a result. Notice that the blue dot in the blue segment of length 3 is placed at position 1, and the blue segment is scaled so that this dot is placed at the end of the red segment (of length 2). For multiplication by any X, the blue dot will always start at 1 and end at X. This works even if X is smaller than 1, or negative.
The opposite of multiplication is division.
Teachers usually require their pupils to memorize the table of the first 9 numbers when teaching multiplication, so that more complex multiplication tasks can be performed. |
Microsoft | Microsoft Corporation (NASDAQ:MSFT) is a company that makes computer software and video games for users around the world. Bill Gates and Paul Allen founded the company in 1975. Microsoft makes Microsoft Windows, Microsoft Office (including Microsoft Word), Edge, MSN and Xbox, among others. Most Microsoft programs cannot be downloaded for free - people have to buy them in a shop or online. Some products (like the Windows operating system) are often already installed when people buy a new computer.
Although Microsoft is best known for its software products, the company also runs a number of web services. They include:
Microsoft has also made a wide variety of hardware over the years. Among them are computer accessories like mice, keyboards, and webcams.
The company also makes and promotes a video game console, Xbox. It lets people play video games on their televisions. The games were first stored on CDs, but many recent games are downloaded from the Internet. There have been three generations of Xbox. The first generation came out in 2001 and was just called Xbox, while the second, the Xbox 360, was released in 2005. The third and newest model is the Xbox One in May 2013. Beginning with the Xbox 360, Microsoft introduced Xbox Live, which lets people play games online against other people anywhere in the world. The Xbox has become very popular and more than 100 million units have been sold worldwide. Because of this, Microsoft is considered one of the three big companies that make video game consoles, along with Nintendo and Sony.
Most recently, Microsoft has also started to make its own PCs, called the Surface. The first model was announced in 2012 and the Surface line now includes tablets that use either ARM or Intel processors, two models of laptops called the Surface Book and Surface Laptop, an all-in-one PC called the Surface Studio, and an interactive whiteboard, the Surface Hub.
In 2014, Microsoft bought the mobile phone division of Nokia, a Finnish company, which then became Microsoft Mobile. The sale included the Lumia family of smartphones, which use Microsoft's own Windows Phone platform. From 2014 to 2016, Microsoft Mobile also made feature phones with the Nokia brand. Then the feature phone business was sold to HMD global, which continues to produce both feature phones and Android smartphones under license from Nokia. |
Islamic world | The Islamic World consists of all people who are in Islam. It is not an exact location, but rather a community. When they do things together as Muslims, they are the "umma", which means "community" referring to all of the believers. The faith emphasizes unity and defense of fellow Muslims, so it is common for these nations to cooperate. Recent conflicts in the Muslim World have sometimes spread because of this desire to cooperate (see below). It is also likely that some have been made shorter and less damaging because of it. Some might even have never started.
Muslims are in many countries. In 52 nations, Muslims are the majority. Almost all are Sunni. They speak about 60 languages and come from all ethnic backgrounds.
The "Al-Jazeera" satellite TV network in the Arabic language is a news source many Muslims watch.
In most Muslim nations, the government is the main source of news. This sometimes makes it very difficult or dangerous to make anti-government statements.
There are, however, many other news programmes and websites in the Muslim world.
Islamic law exists in many variations - in Arabic it is called shariah - five schools of which were created centuries ago. These are the classical fiqh: the Hanafi school from India, Pakistan and Bangaladesh, West Africa, Egypt, the Maliki in North Africa and West Africa, the Shafi in Malaysia and Indonesia, the Hanbali in Arabia, and Jaferi in Iran and Iraq - where the majority is Shia. All five are very old and many Muslims feel a new fiqh must be created for modern society. Islam has a method for doing this, al-urf and ijtihad are the words to describe this method, but they have not been used in a long time, and few people are trusted enough to use them to make new laws.
So, in most of the Muslim world, people are very conservative, especially about alcohol, adultery, abortion and women working in jobs where they are used to lure customers.
Muslim women often dress extremely modestly, and many do so by choice. But in some countries they have been forced to do so against their will. This is one of the things that causes tension between the Western World and that of Muslims.
Islamic economics bans debt but in most Muslim countries Western banking is allowed. This is another issue that many Muslims have with the Western world.
One quarter of the world population share Islam as an ethical tradition.
Many people in these countries also see Islam as a political movement. In democratic countries there is usually at least one Islamic party.
Political Islam is powerful in all Muslim-majority countries. Islamic parties in Pakistan and Algeria have taken power.
Many in these movements call themselves Islamists, which also sometimes describes more militant Islamic groups. The relationships between these groups and their views of democracy are complex.
Some of these groups are called terrorists because they attack civilians of other non-Muslim nations, to make a political point.
Israel is very unpopular in the Muslim world, because of the Israeli-Palestinian conflict and the way that the state of Israel came into being in 1948 which many Arabs thought was unfair.
Some Muslims see this as a fight against Judaism or Jews, but not all. In Morocco for instance, the Islamists recently invited Jews to join the party. Jewish groups also cooperate with Arabs in the West Bank, where Neturei Karta (anti-Zionist orthodox Jewish) leader Rabbi Mosche Hirsch served as the Minister for Jewish Affairs in the Fatah before there was a Palestinian Authority. Like the Arabs, this small group of Jews thought the way Israel was created was not right. However, very few Jews believe this, and most support Israel as a state.
In 1979 there was a big shift in the way the Muslim world dealt with the rest of the world. In that year, Egypt made peace with Israel, Iran became an Islamic state after a revolution, and there was an invasion of Afghanistan by the Soviet Union. A lot of things changed in that year. By 2001 the Soviet Union was gone, Jordan had also made peace with Israel, and on September 11, 2001 there were major attacks on the U.S. - which most people believe were made to drive the United States out of the Muslim world, especially Saudi Arabia. In many ways the events of 1979 led to the events of 2001.
The 2001 invasion of Afghanistan and 2003 invasion of Iraq are called part of a War on Terrorism by the United States. Many or most Muslims see it as a War on Islam. After the invasion, the Islamic parties won more seats, and a majority of Muslims polled in many nations expressed support for Osama bin Laden and said he would "do the right thing". Olivier Roy is a French scholar who thinks that this does not express support for al-Qaeda or militant Islam but opposing colonialism and what many Muslims call racism - favourable treatment for Jews especially those living in West Bank settlements, many of whom have American or British passport, and which the United Nations says have no right to live there.
The situation is very complicated and there are many different views of it.
The Organization of Islamic Conference formed in 1969 lets the Muslim nations work as a group. Russia joined in 2003.
The Arab League is a smaller group of only the Arab countries.
OPEC is another forum where issues between the Muslim and non-Muslim world come up. In 1973 to protest U.S. support for Israel there was an oil embargo which caused the 1973 energy crisis. |
Multiverse | A multiverse is the theory of a conjectured set of multiple possible universes, including ours, which make up reality. These universes are sometimes called parallel universes. A number of different versions have been considered.
The term "multiverse" was coined in 1895 by psychologist William James as a philosophical concept.
The cosmological multiverse tries to explain why the universe we observe i.e. <nowiki>"our universe"</nowiki> seems so welcoming to the emergence of life. Even small changes to the way physics works would make life impossible. In a multiverse a vast number of universes are randomly created and some happen to favour life emerging there. Many inhospitable universes would also have been created, but there would be no life there to observe their existence.
The quantum multiverse is another version in which our universe splits into alternative futures with every quantum event. This is called many-worlds interpretation of quantum mechanics. |
Mechanistic paradigm | The mechanistic paradigm, also known as the Newtonian paradigm, assumes that things in the environment around humans are more like machines than like life. It was more common in the 19th century. This is a set of loosely related beliefs that affects all sciences:
Believers in this paradigm sometimes say that those who do not believe in it are following a cognitive paradigm - but almost no one uses this term, since it is redundant - cognitive science is already accepted as the most basic idea in the philosophy of science. But mechanists reject some of the ideas of cognitive scientists, like cognitive science of mathematics.
Mechanistic thinking also assumes that philosophy of perception is much less important than cognitive scientists say it is - that humans and their beliefs and equipment do not generally add a lot of bias to a scientific theory. Thomas Kuhn said otherwise, that these things matter, and that the major assumptions of science, can shift drastically. This he called a paradigm shift. The shift from mechanistic to cognitive paradigm is an example of this.
Later he used other words to describe the assumptions and beliefs, like mind-set, but the word "paradigm" is still used. Some say it is much over-used.
Economics is often said to "suffer from" assumptions of the mechanistic paradigm. Sometimes those who believe in neoclassical economics and also in the mechanistic paradigm say they "seek to unify physics and economics," as if people and particles behaved as two examples of the same kind of thing.
Technology is often easier to make if people accept a mechanistic paradigm - but it may be harder to say why it does not work, if one believes in these ideas. For instance, creating diagnostic trees might be easier if one works from experience, not from an idea of how a technology should or must work.
A controversial idea is that mechanistic ideas are just an older idea called scholasticism, with more mathematics. Both tried to work from what should or must be, instead of what experiment seemed to show.
Another controversial idea is that scientism, belief in science as if it were a religion or ethical tradition, comes from this paradigm. Most scientists who are mechanistic do not say they see science as a guide to ethics, but try to keep them separate. |
MediaWiki | MediaWiki is the name of the software that runs all of the Wikimedia projects. MediaWiki was released in 2003. It is free server-based software which is licensed under the GNU General Public License (GPL). The software is licensed under the GPL. This means it is free content, or open source.
MediaWiki is designed to be run on a large web server farm for a website that gets millions of hits per day. MediaWiki is a very powerful, scalable software and a feature-rich wiki implementation, that uses PHP to process and display data stored in its MySQL database. Pages use MediaWiki's Wikitext format, so that users without knowledge of XHTML or CSS can edit them easily.
When a user submits an edit to a page, MediaWiki writes it to the database, but without deleting the previous versions of the page, thus allowing easy reverts in case of vandalism or spamming. MediaWiki can manage image and multimedia files, too, which are stored in the filesystem. For large wikis with lots of users, MediaWiki supports caching and can be easily coupled with Squid proxy server software.
All Wikimedia projects run on MediaWiki version .
Because MediaWiki is flexible, many websites that want people to contribute information use MediaWiki rather than other types of wiki software. Those operated by Wikia are among them.
There are also some websites that use MediaWiki as a content management system.
In MediaWiki, a system administrator can choose to install extensions which are provided on the main MediaWiki website. Some are from the MediaWiki developers, while others are from programmers from all around the world.
Most extensions can be download from Wikimedia's Subversion repository. However, there are some other extensions that other people host themselves.
Some extensions had been added to the main software along the development of MediaWiki. For example, the extension is an extension to promote a user into an administrator or a bureaucrat.
There were a total of 2124 extensions as of October 4, 2013.
In the default installation of MediaWiki, the software has 17 namespaces(18 actually, but one does not have a namespace), namely:
Additional namespaces can be added using the from the installation of MediaWiki.
As MediaWiki is a complex software, there would always be bugs in the software, especially for new extensions. Therefore, Wikimedia has created a bugzilla website for people who see a bug to tell the developers of MediaWiki.
Some extensions of MediaWiki use the , while some just use the talk pages of the extension page.
Users can customize MediaWiki for different appearance. They may use one of the several "skins". At different times different skins have been default. For example, Wikipedia once used Monobook before adopting the new Vector skin in version 1.16.
A survey done by Wikimedia showed that more people prefer the Vector skin.
"More information about the software:" |
First language | A first language (also mother tongue, native language, arterial language, or L1) often means the language that a person learns first. It helps one understand words and concepts in the style of that language.
Sometimes, "first language" means the language that a person speaks best (the second language is then spoken less well than the first language, etc.). Since "first language", "second language" and "third language" then mean how well one speaks a language, a person can have more than one first language or second language. |
Mustache | The hair that grows on the upper lip of some men is called a mustache. The hair that grows on the sides of the face and the chin of some men is called a beard. Some men have a lot of hair and a big mustache, and some have very little. In the modern world, many men shave part or all of their mustaches, or cut their mustache so it does not get very long. A chin beard with no mustache is called a goatee, whilst a chin beard with a mustache is known as a Van Dyke.
Mustache in United Kingdom and Commonwealth of Nations is spelled moustache.
Some animals such as walruses also have hair like this, and people sometimes also call this hair a mustache. |
Mile | A mile is a unit of length. There are many different kinds of mile but "mile" on its own usually means the "statute" mile.
In the US and the UK the word "mile" usually means the statute mile.
The nautical mile is used for sea or air travel.
The nautical mile was originally defined as one minute of arc along a line of longitude of the Earth. There are 60 minutes of arc in one degree or arc (60' = 1°). So there were 10,800 nautical miles from the North Pole to the South Pole.
Now the nautical mile is defined as 1,852 metres.
The speed of a ship that travels one nautical mile in one hour is called one knot
The mile was first used by the Romans. It comes from the Latin phrase "mille passus" (plural: "milia passuum"). This means "one thousand paces". A pace is the distance each foot moves when taking one step.
Different miles have been used throughout history in various parts of the world. In Norway and Sweden, for example, a mil is a unit of length which is equal to 10 kilometres.
Even in English-speaking countries that use the metric system (for example, Australia, Canada, and New Zealand), the mile is still used in many idioms. These include: |
Margarine | Margarine is an artificial butter. It can be made from vegetable oil, or animal fat. It may also contain skimmed milk, salt and emulsifiers. Margarine is used in many baked products. It contains less fat than butter, so is often chosen instead of it. There are also "low fat" margarines, which contain even less fat. However, many types of margarine contain trans fats, which are unhealthy and can cause heart disease and also contain unstable Omega-6 levels. Other fats, like olive oil, and butter, are a better choice for cooking. |
Milky Way | The Milky Way is our home galaxy. It contains over 200 billion stars, including our Sun.
The Milky Way has a diameter of about 170,000 or 200,000 light years, and is a barred spiral galaxy. The idea that the Milky Way is made of stars goes back to the Ancient Greek philosopher Democritus.
The Milky Way has three main parts: a "disk", where the Solar System is, a "bulge" at the core, and an outer "halo" all around it. Although the word "disk" suggests it is flat, the Milky Way is actually not quite flat. It is slightly warped and twisted.
This galaxy belongs to the Local Group of three large galaxies and over 50 smaller galaxies. The Milky Way is one of the largest galaxies in the group, second to the Andromeda Galaxy. Its closest neighbour is the Canis Major Dwarf Galaxy, which is about 25,000 light years away from the Earth. The Andromeda Galaxy is moving towards the Milky Way Galaxy, and will collide with it in about 3.75 billion years. The Andromeda Galaxy moves with a speed of about 1,800 kilometres per minute.
The stellar disk of the Milky Way Galaxy is about 200,000 light-years (9×10 km) in diameter, and is considered to be, on average, about 1000 light years thick.
It is estimated to contain at least 100 billion stars, and possibly up to 400 billion stars. The figure depends on the number of very low-mass, or dwarf stars, which are hard to detect, especially more than 300 light years from our sun. Therefore, present estimates of the total number are uncertain. This can be compared to the one trillion (10) stars of the neighbouring Andromeda Galaxy.
The stellar disc of the Milky Way does not have a sharp edge, a radius beyond which there are no stars. Rather, the number of stars drops smoothly with distance from the centre of the Galaxy. Beyond a radius of about 40,000 light years, the number of stars drops much faster, for reasons that are not understood.
Extending beyond the stellar disk is a much thicker disk of gas. Recent observations indicate that the gaseous disk of the Milky Way has a thickness of around 12000 light years–twice the previously accepted value. As a guide to the relative physical scale of the Milky Way, if the Solar System out to the orbit of Pluto were reduced to the size of a US quarter (about an inch or 25 mm in diameter), the Milky Way would have a diameter of 2,000 kilometers. At 220 kilometers per second it takes the Solar System about 240 million years to complete one orbit of the Galaxy (a galactic year).
The Galactic halo extends outward, but is limited in size by the orbits of two Milky Way satellites, the Large and the Small Magellanic Clouds, whose closest approach is at about 180,000 light years. At this distance or beyond, the orbits of most halo objects would be disrupted by the Magellanic Clouds, and the objects would likely be ejected from the vicinity of the Milky Way.
The galactic disc, which bulges outward at the galactic center, has a diameter of 170–200,000 light years.
The exact distance from the Sun to the galactic center is debated. The latest estimates give distances to the Galactic center of 25–28,000 light years.
Movement of material around the galactic center shows that it has a compact object of very large mass. The intense radio source named Sagittarius A*, thought to mark the center of the Milky Way, is now confirmed to be a supermassive black hole. Most galaxies are believed to have a supermassive black hole at their center.
The nature of the galaxy's bar is also actively debated, with estimates for its half-length and orientation spanning from 3,300–16,000 light years (short or a long bar) and 10–50 degrees. Viewed from the Andromeda Galaxy, it would be the brightest feature of our own galaxy.
In Greek mythology, Zeus places his son (the baby Heracles) whose mother was a mortal woman on Hera's breast while she is sleeping so that the baby will drink her divine milk and become immortal. However, Hera wakes up while she is breastfeeding the baby and realizes she is nursing a baby she does not know. According to Greek mythology, she then pushes the baby away and a stream of her milk sprays the night sky, making a faint band of light known as the Milky Way. |
Movement | Movement, or motion, is the state of changing something's position—that is, changing where something is. A flying bird or a walking person are moving, because they change where they are from one place to another. There are many kinds of science and math related to movement.
Thanks to the work of scientists including Galileo Galilei and Issac Newton, we know that "position" and motion are relative. This means that an object's position depends on where it exists in relation to other objects. For example, a ball can be 5 feet away from a box, 3 feet away from a chair, and a foot away from a table. Here, the box, chair and the table helped me to decide the position of the ball. In other words, they acted as the reference points for my observation. By telling you how far the ball was from other objects, I told you its relative position.
Similarly, an object's "motion" is also relative. It depends on how its position changes in relation to other objects. Let us understand this with an example:
Suppose you are sitting inside a train. The train has not started moving yet. Let us call this Train A. You look out from the window and see another train moving in the opposite direction. Let us call this Train B. Now, when you look at Train B, it appears as if Train A is moving in the forward direction. But when you look at a nearby electric pole, you notice that train A was actually at rest and Train B was moving backwards.
From this, we conclude that we cannot decide whether a body is moving or at rest, unless we choose a frame of reference. In the above example, when we chose Train B as our frame of reference, Train A appeared to be moving forward. On the other hand, when we chose the electric pole as frame of reference, Train A appeared to be at rest and Train B appeared to move backward.
The study of motion, without considering its cause is called kinematics. In kinematics, we come across terms like speed, velocity, and acceleration. Dynamics is the branch of physics concerned with the study of causes and effects of motion. In dynamics we come across terms like force, inertia, work, energy and momentum. |
Metaphor | Metaphor is a term for a figure of speech. It does not use a word in its basic literal sense. Instead, it uses a word in a kind of comparison. We run, and we also say rivers run. We may run into trouble, especially if we run up a bill at the bar.
So a metaphor uses words to make a picture in our mind. It takes a word from its original context, and uses it in another.
Metaphors are an essential part of language: it is not possible to speak or write without them. A simple example is the word "run". This has a basic meaning of "moving quickly" or "go with quick steps on alternate feet, never having both feet on the ground at the same time". The "Concise Oxford Dictionary" then gives
34 other uses as a verb; 21 uses as a noun; about 50 uses in short phrases. All of these are metaphors, although we do not usually notice this.
We use metaphors to make "indirect" comparisons, but without using 'like' or 'as' – because that would be a simile. A simile is a "direct" comparison: "Jane is like a child".
A metaphor very often uses the verb 'to be': "love "is" war", for example, not "love "is like" war" (that is a simile).
Poetry includes much metaphor, usually more than prose.
Spam is an example that any email user knows about – this word was originally a metaphor, from 'Spam', a type of canned meat. Servers putting unwanted email into somebody's inbox was similar to waiters putting unwanted Spam into food. This was originally suggested by a Monty Python scene. When we use a metaphor very often and we forget the old meaning, or forget that the two meanings are connected, this is a 'dead metaphor'.
Originally "metaphor" was a Greek word for 'transfer'. It came from "meta" ('beyond') and "pherein" ('carry'). So the word "metaphor" in English was a metaphor, too. Today in Greek, "metaphor" is a trolley (a thing that is pushed for carrying shopping or bags).
A simple metaphor has a single link between the subject and the metaphoric vehicle. The vehicle thus has a single meaning which is transferred directly to the subject.
In the simple metaphor, the effort to understand what the author or speaker intends is relatively low, and hence it may easily be used with a wider and less sophisticated audience.
A complex metaphor happens where a simple metaphor is based on a secondary metaphoric element. For example, using a metaphor of 'light' for 'understanding' may be complexified by saying 'throwing light' rather than 'shining light'. 'Throwing' is an extra metaphor for how light arrives.
A compound metaphor is one where there are multiple parts in the metaphor that are used to snag the listener. These parts may be enhancement words such as adverbs, adjectives, etc.
Each part in the compound metaphor may be used to signify an additional item of meaning.
Compound metaphors are like a multiple punch, hitting the listener repeatedly with metaphoric elements. Where the complex metaphor uses stacked layers to enhance the metaphor, the compound metaphor uses sequential words. The compound metaphor is also known as a loose metaphor.
A live metaphor is one which a reader notices. A dead metaphor is one no-one notices because it has become so common in the language.
Two people walk off a tennis court. Someone asks the loser: "What happened?". |
Metabolism | Metabolism is the chemical reactions which keep us alive. It happens in the cells of living organisms.
Reactions catalyzed by enzymes allow organisms to grow, reproduce, maintain their structures, and respond to their environments. The word ‘metabolism’ can also refer to digestion and the transport of substances into and between different cells.
Metabolism is usually divided into two categories. Catabolism breaks down organic matter and harvests energy by way of cellular respiration. Anabolism uses energy to construct molecules such as proteins and nucleic acids.
The chemical reactions of metabolism are organized into metabolic pathways, or cycles, like the Krebs cycle. One chemical is transformed through a series of steps into another chemical by a series of enzymes.
The metabolic system of an organism decides which substances it finds nutritious and which poisonous. For example, some prokaryotes use hydrogen sulfide as a nutrient, yet this gas is poisonous to animals. The speed of metabolism, the metabolic rate, influences how much food an organism will need, and how it is able to get that food.
A striking feature of metabolism is the similarity of the basic metabolic pathways and components between even vastly different species. For example, the set of carboxylic acids that are best known as the intermediates in the citric acid cycle are present in all known organisms, being found in species as diverse as the unicellular bacterium "Escherichia coli" and huge multicellular organisms like elephants. These striking similarities in metabolic pathways are likely due to their early appearance in the evolution of life, and kept because of their efficiency. |
Microscope | A microscope is a scientific instrument. It makes small objects look larger. This lets people see the small things. People who use microscopes frequently in their jobs include doctors and scientists. Students in science classes such as biology also use microscopes to study small things.
The earliest microscopes had only one lens and are called "simple microscopes". "Compound microscopes" have at least two lenses. In a compound microscope, the lens closer to the eye is called the "eyepiece". The lens at the other end is called the "objective". The lenses multiply up, so a 10x eyepiece and a 40x objective together give 400x magnification.
Microscopes make things seem larger than they are, to about 1000 times larger. This is much stronger than a magnifying glass which works as a simple microscope.
There are many types of microscopes. The most common kind of microscope is the compound light microscope. In a compound light microscope, the object is illuminated: light is thrown on it. The user looks at the image formed by the object. Light passes through two lenses and makes the image bigger.
The second most common kind are a few kinds of electron microscopes. Transmission electron microscopes (TEMs) fire cathode rays into the object being looked at. This carries information about how the object looks into a magnetic "lens". The image is then magnified onto a television screen. Scanning electron microscopes also fire electrons at the object, but in a single beam. These lose their power when they strike the object, and the loss of power results in something else being generated—usually an X-ray. This is sensed and magnified onto a screen. Scanning tunneling microscopes were invented in 1984.
A fluorescence microscope is a special kind of light microscope. In 2014, the Nobel Prize in Chemistry was awarded to Eric Betzig, William Moerner, and Stefan Hell for "the development of super-resolved fluorescence microscopy". The citation says it brings "optical microscopy into the nanodimension". |
Mass | The mass of an object is a measure of the amount of matter in a body. A mountain has typically more mass than a rock, for instance. Mass should not be confused with the related but quite different concept of weight.
We can measure the mass of an object if a force acts on the object. If the mass is greater, the object will have less acceleration (change in its motion). This measure of mass is called "inertial mass" because it measures inertia.
A large mass like the Earth will attract a small mass like a human being with enough force to keep the human being from floating away. "Mass attraction" is another word for gravity, a force that exists between all matter. When we measure the force of gravity from an object, we can find its "gravitational mass". Tests of inertial and gravitational mass show that they are the same or almost the same.
The unit of mass in the International System of Units is the kilogram, which is represented by the symbol 'kg'. Fractions and multiples of this basic unit include the gram (one thousandth of a kg, symbol 'g') and the tonne (one thousand kg), amongst many others.
In some fields or applications, it is convenient to use different units to simplify the discussions or writings. For instance,
Traditional units are still in encountered in some countries: imperial units such as the ounce or the pound were in widespread use within the British Empire. Some of them are still popular in the United States, which also uses units like the short ton (2,000 pounds, 907 kg) and the long ton (2,240 pounds), not to be confused with the metric tonne (1,000 kg).
Mass is an intrinsic property of the object: it does not depend on its volume, or position in space, for instance. For a long time (at least since the works of Antoine Lavoisier in the second half of the eighteen century), it has been known that the sum of the masses of objects that interact or of the chemicals that react remain conserved throughout these processes. This remains an excellent approximation for everyday life and even most laboratory work.
However, Einstein has shown through his special theory of relativity that the mass "m" of an object moving at speed "v" with respect to an observer must be higher than the mass of the same object observed at rest "m" with respect to the observer. The applicable formula is
formula_1
where "c" stands for the speed of light. This change in mass is only important when the speed of the object with respect to the observer becomes a large fraction of "c". |
Mercury (planet) | Mercury is the smallest planet in the Solar System. It is the closest planet to the sun. It makes one trip around the Sun once every 87.969 days. Mercury is bright when it is visible from Earth, ranging from −2.0 to 5.5 in apparent magnitude. It cannot be easily seen as it is usually too close to the Sun. Because Mercury is normally lost in the glare of the Sun, Mercury can only be seen in the morning or evening twilight or during a solar eclipse.
Less is known about Mercury than about other planets of our Solar System. Telescopes on the Earth show only a small, bright crescent, and putting a satellite in orbit around it is difficult. The first of two spacecraft to visit the planet was Mariner 10, which mapped only about 45% of the planet’s surface from 1974 to 1975. The second is the MESSENGER spacecraft, which finished mapping the planet in March 2013.
Mercury looks like Earth's Moon. It has many craters and areas of smooth plains, no moons around it and no atmosphere as we know it. However, Mercury does have an extremely thin atmosphere, known as an exosphere. Unlike Earth's Moon, Mercury has a large iron core, which gives off a magnetic field about 1% as strong as that of the Earth. It is a very dense planet due to the large size of its core. Surface temperatures can be anywhere from about 90 to (−183 °C to 427 °C, −297 °F to 801 °F), with the subsolar point being the hottest and the bottoms of craters near the poles being the coldest.
Known sightings of Mercury date back to at least the first millennium BC. Before the 4th century BC, Greek astronomers thought that Mercury was two different objects: one able to be seen only at sunrise, which they called Apollo; the other that was only able to be seen at sunset, which they called Hermes. The English name for the planet is from the Romans, who named it after the Roman god Mercury, which they thought to be the same as the Greek god Hermes. The symbol for Mercury is based on Hermes' staff.
Even though Mercury is the closest planet to the Sun, it is not the warmest. This is because it has no greenhouse effect, so any heat that the Sun gives to it quickly escapes into space. The hottest planet is Venus.
Mercury is one of four inner planets in the Solar System, and has a rocky body like the Earth. It is the smallest planet in the Solar System, with a radius of . Mercury is even smaller than some of the largest moons in the solar system, such as Ganymede and Titan. However, it has a greater mass than the largest moons in the solar system. Mercury is made of about 70% metallic and 30% silicate material. Mercury's density is the second highest in the Solar System at 5.427 g/cm³, only a little bit less than Earth’s.
Mercury's surface looks similar to the surface of the Moon. It has plains that look like mares and has lots of craters. Mercury was hit by a lot of comets and asteroids 4.6 billion years ago. Mercury was also hit during a period called the Late Heavy Bombardment. Mercury has lots of craters because it does not have any atmosphere to slow objects down. Images gotten by "MESSENGER" have shown that Mercury may have shield volcanoes.
The surface temperature of Mercury ranges from 100 to 700 K (−173 to 427 °C; −280 to 800 °F) at the most extreme places. Even though the temperature at the surface of Mercury in the day is very high, observations suggest that there is frozen water on Mercury.
Mercury is too small and hot for its gravity to keep any thick atmosphere for a long time. It does have a thin exosphere that contains hydrogen, helium, oxygen, sodium, calcium, potassium. This exosphere is lost and replenished from lots of sources. Hydrogen and helium may come from the solar wind. Radioactive decay of elements inside the crust of Mercury is another source of helium, and also sodium and potassium.
Mercury has the most eccentric orbit of all the planets; its eccentricity is 0.21. Its distance from the Sun ranges from 46,000,000 to 70,000,000 km (29,000,000 to 43,000,000 mi). It takes 87.969 Earth days to go around the Sun. Mercury's axial tilt is 0.027 degrees which is best measurement of the axial tilt.
Many man-made satellites have been sent to Mercury to study it. They are:
The first spacecraft to visit Mercury was NASA's Mariner 10. It stayed in Mercury's orbit from 1974–1975. Mariner 10 provided the first close-up pictures of Mercury's surface. It showed many types of geological features, such as the craters. Unfortunately, the same face of the planet was day at each time Mariner 10 flew close to Mercury. This made close observation of both sides of the planet impossible. In the end, less than 45% of the planet's surface was mapped.
The Mariner 10 came close to Mercury three times. At the first time, instruments found a magnetic field, which surprised planetary geologists because Mercury's rotation was too slow to generate a magnetic field. The second time was mainly used to take pictures of Mercury's surface. At the third time, more information about the magnetic field were obtained. It showed that the planet's magnetic field is much like Earth's.
On March 24, 1975, just eight days after its final close approach, Mariner 10 ran out of fuel. Because its orbit could no longer be controlled, mission controllers instructed the probe to shut down. Mariner 10 is thought to still be orbiting the Sun.
The second satellite to reach Mercury is NASA's MESSENGER. It stands for MErcury Surface, Space ENvironment, GEochemistry, and Ranging. It was launched on August 3, 2004. It made a fly-by of Earth in August 2005. It made another fly-by of Venus in October 2006. It made its first fly-by of Mercury happened on January 14, 2008, a second on October 6, 2008, and a third on September 29, 2009. Most of the hemisphere not mapped by "Mariner 10" was mapped during these fly-bys. The satellite entered an elliptical orbit around the planet on March 18, 2011. The first image of Mercury orbiting the Sun was gotten on March 29, 2011.
MESSENGER was made to study Mercury's high density, the history of Mercury's geology, its magnetic field, the structure of its core, whether it has ice at its poles, and where its thin atmosphere comes from. "MESSENGER" crashed into Mercury's surface on April 30, 2015.
The European Space Agency and the Japanese Space Agency developed and launched a joint mission called "BepiColombo." It will orbit Mercury with two probes: one to map the planet and the other to study its magnetosphere. It was launched on October 20, 2018. "BepiColombo" is expected to reach Mercury in 2025. It will release the probe that will study the magnetosphere into an elliptical orbit. It will then release the probe the will make a map of Mercury into a circular orbit. |
Mars | Mars is the fourth planet from the Sun in the Solar System and the second smallest planet. Mars is a cold terrestrial planet with polar ice caps of frozen water and carbon dioxide. It has the largest volcano in the Solar System, which is known as Olympus Mons, and some very large impact craters. Mars is named after the mythological Roman god of war because it appears of red color.
Space probes such as the Viking program landers are the main tools for the exploration of Mars.
It is sometimes known as the red planet
Mars is a terrestrial planet and made of rock. The ground there is red because of iron oxide (rust) in the rocks and dust. The planet's atmosphere is very thin. It is mostly carbon dioxide with some argon and nitrogen and tiny amounts of other gases including oxygen. The temperatures on Mars are colder than on Earth, because it is farther away from the Sun and has less air to keep heat in. There is water ice and frozen carbon dioxide at the north and south poles. Mars does not have any liquid water on the surface now, but signs of run-off on the surface were probably caused by water.
The average thickness of the planet's crust is about 50 km (31 mi), with a maximum thickness of 125 km (78 mi).
Mars has two small moons, called Phobos and Deimos.
The origin of Mars' moons is unknown and controversial. One theory is that the moons are captured asteroids. However, the moons' near circular orbits and low inclination relative to the Martian equator are not in agreement with the capture hypothesis.
Estimates of the mass ejected by a large Borealis-size impact vary. Simulations suggest that a body about 0.02 of Mars mass (~0.002 Earth mass) in size can produce a sizable debris disk in Martian orbit. Much of the material would stay close to Mars. There are several other large impact basins on Mars that could also have ejected enough debris to form the moons.
In the next billion years, Phobos will probably be reformed into a ring around Mars.
Mars does not have a global magnetic field. Despite this, observations show that parts of the planet's crust have been magnetized. This suggests that polarity reversals have occurred in the past. This paleomagnetism is similar to the magnetic striping found on Earth's ocean floors. One theory is that these bands suggest plate tectonic activity on Mars four billion years ago, before the planetary dynamo stopped working and the planet's magnetic field faded.
A Martian day is called a "sol", and is a little longer than an Earth day. Mars rotates in 24 hours and 37 minutes. It rotates on a tilted axis, just like the Earth does, so it has four different seasons. Of all the planets in the Solar System, the seasons of Mars are the most Earth-like, due to their similar axial tilt. The lengths of the Martian seasons are almost twice those of Earth's, as Mars's greater distance from the Sun leads to the Martian year being almost two Earth years long.
Martian surface temperatures vary from lows of about (at the winter polar caps) to highs of up to (in equatorial summer). The wide range in temperatures is due mostly to the thin atmosphere which cannot store much solar heat. The planet is also 1.52 times as far from the Sun as Earth, resulting in just 43% of the amount of sunlight.
A 2015 report says Martian dark streaks on the surface were affected by water.
Liquid water cannot exist on the surface of Mars due to its low atmospheric pressure (there's not enough air to hold it in), except at the lowest elevations for short periods. The two polar ice caps appear to be made largely of frozen water. The amount of ice in the south polar ice cap, if melted, would be enough to cover the entire planet's surface 11 meters deep. A permafrost mantle stretches from the pole to latitudes of about 60°.
Geological evidence gathered by unmanned missions suggest that Mars once had much liquid water on its surface. In 2005, radar data revealed the presence of large quantities of water ice at the poles, and at mid-latitudes. The Mars rover "Spirit" sampled chemical compounds containing water molecules in March 2007. The "Phoenix" lander found water ice in shallow Martian soil in July 2008.
Landforms seen on Mars strongly suggest that liquid water at some time existed on the planet's surface. Huge areas of ground have been scraped and eroded.
Mars has two permanent polar ice caps. During a pole's winter, it lies in continuous darkness, chilling the surface and causing the deposition of 25–30% of the atmosphere into slabs of CO ice (dry ice). When the poles are again exposed to sunlight, the frozen CO sublimes (turns to vapor), creating enormous winds that sweep off the poles as fast as 400 km/h. Each season this moves large amounts of dust and water vapor, giving rise to Earth-like frost and large cirrus clouds and dust storms. Clouds of water-ice were photographed by the "Opportunity" rover in 2004.
The polar caps at both poles consist primarily of water ice.
Mars has a very thin atmosphere with barely any oxygen (it is mostly carbon dioxide). Because there is an atmosphere, however thin it is, the sky does change colour when the sun rises and sets. The dust in the Martian atmosphere makes Martian sunsets somewhat blue. Mars's atmosphere is too thin to protect Mars from meteors, which is part of the reason why Mars has so many craters.
After the formation of the planets, all experienced the "Late Heavy Bombardment". About 60% of the surface of Mars shows a record of impacts from that era. Much of the remaining surface is probably lying over the immense impact basins caused by those events. There is evidence of an enormous impact basin in the northern hemisphere of Mars, spanning , or roughly four times larger than the largest impact basin yet discovered. This theory suggests that Mars was struck by a Pluto-sized body about four billion years ago. The event is thought to be the cause of the difference between the Martian hemispheres. It made the smooth Borealis Basin that covers 40% of the planet.
Some meteorites hit Mars with so much force a few pieces of Mars went flying into space even to Earth! Rocks on Earth are sometimes found which have chemicals that are exactly like the ones in Martian rocks. These rocks also look like they fell really quickly through the atmosphere, so it is reasonable to think they came from Mars.
Mars is home to the highest known mountain in the Solar System, Olympus Mons. Olympus Mons is about 17 miles (or 27 kilometres) high. This is more than three times the height of Earth's tallest mountain, Mount Everest. It is also home to Valles Marineris, the third largest rift system (canyon) in the Solar System, 4,000 km long.
Our records of watching and recording Mars start with ancient Egyptian astronomers in the 2nd millennium BC.
Detailed observations of the location of Mars were made by Babylonian astronomers who developed methods using math to predict the future position of the planet. The ancient Greek philosophers and astronomers developed a model of the solar system with the Earth at the center ('geocentric'), instead of the sun. They used this model to explain the planet's motions. Indian and Islamic astronomers estimated the size of Mars and its distance from Earth. Similar work was done by Chinese astronomers.
In the 16th century, Nicholas Copernicus proposed a model for the Solar System in which the planets follow circular orbits about the Sun. This 'heliocentric' model was the beginning of modern astronomy. It was revised by Johannes Kepler, who gave an elliptical orbit for Mars which better fit the data from our observations.
The first observations of Mars by telescope was by Galileo Galilei in 1610. Within a century, astronomers discovered distinct albedo features (changes in brightness) on the planet, including the dark patch and polar ice caps. They were able to find the planet's day (rotation period) and axial tilt.
Better telescopes developed early in the 19th century allowed permanent Martian albedo features to be mapped in detail. The first crude map of Mars was published in 1840, followed by better maps from 1877 onward. Astronomers mistakenly thought they had detected the spectroscopic mark of water in the Martian atmosphere, and the idea of life on Mars became popular among the public.
Yellow clouds on Mars have been observed since the 1870s, which were windblown sand or dust. During the 1920s, the range of Martian surface temperature was measured; it ranged from 85 to 7 C. The planetary atmosphere was found to be arid with only traces of oxygen and water. In 1947, Gerard Kuiper showed that the thin Martian atmosphere contained extensive carbon dioxide; roughly double the quantity found in Earth's atmosphere. The first standard naming of Mars surface features was set in 1960 by the International Astronomical Union.
Since the 1960s, multiple robotic spacecraft and rovers have been sent to explore Mars from orbit and the surface. The planet has remained under observation by ground and space-based instruments across a broad range of the electromagnetic spectrum (visible light, infrared and others). The discovery of meteorites on Earth that came from Mars has allowed laboratory examination of the chemical conditions on the planet.
During the 1984 opposition, Italian astronomer Giovanni Schiaparelli used a telescope to help produce the first detailed map of Mars. What caught people's attention was that the maps had features he called "canali". These were later shown to be an optical illusion (not real). These "canali" were supposedly long straight lines on the surface of Mars to which he gave names of famous rivers on Earth. His term "canali" was popularly mistranslated in English as "canals", and thought to be made by intelligent beings.
Other astronomers thought they could see the canals too, especially the American astronomer Percival Lowell who drew maps of an artificial network of canals on Mars.
Although these results were widely accepted, they were contested. Greek astronomer Eugène M. Antoniadi and English naturalist Alfred Russel Wallace were against the idea; Wallace was extremely outspoken. As bigger and better telescopes were used, fewer long, straight "canali" were observed. During an observation in 1909 by Flammarion with a telescope, irregular patterns were observed, but no "canali" were seen.
Because Mars is the one of the closest planets to Earth in the Solar System, many have wondered if there is any kind of life on Mars. Today we know that the kind of life, if any, would be some simple bacteria-type organism.
NASA maintains a catalog of 34 Mars meteorites, that is, meteorites which originally came from Mars. These assets are highly valuable since they are the only physical samples available of Mars.
Studies at NASA's Johnson Space Centre show that at least three of the meteorites contain possible evidence of past life on Mars, in the form of microscopic structures resembling fossilized bacteria (so-called biomorphs). Although the scientific evidence collected is reliable, and the rocks are correctly described, what made the rocks look like they do is not clear. To date, scientists are still trying to agree if it really is evidence of simple life on Mars.
Over the past few decades, scientists have agreed that when using meteorites from other planets found on Earth (or rocks brought back to Earth), various things are needed to be sure of life. Those things include:
For people to agree on past life in a geologic sample, most or all of these things must be met. This has not happened yet, but investigations are still in progress. Re-examinations of the biomorphs found in the three Martian meteorites are underway.
Liquid water is necessary for life and metabolism, so if water was present on Mars, the chances of life evolving is improved. The Viking orbiters found evidence of possible river valleys in many areas, erosion and, in the southern hemisphere, branched streams. Since then, rovers and orbiters have also looked closely and eventually proved water was on the surface at one time, and is still found as ice in the polar ice caps and underground.
So far, scientists have not found life on Mars, either living or extinct. Several space probes have gone to Mars to study it. Some have orbited (gone around) the planet, and some have landed on it. There are pictures of the surface of Mars that were sent back to Earth by the probes. Some people are interested in sending astronauts to visit Mars. They could do a better search, but getting astronauts there would be difficult and expensive. The astronauts would be in space for many years, and it could be very dangerous because of radiation from the sun. So far we have only sent unmanned probes.
The most recent probe to the planet is the Mars Science Laboratory. It landed on Aeolis Palus in Gale Crater on Mars on 6 August 2012. It brought with it a mobile explorer called 'Curiosity'. It is the most advanced space probe ever. Curiosity has dug up Martian soil and studied it in its laboratory. It has found sulfur, chlorine, and water molecules.
Some famous stories were written about this idea. The writers used the name "Martians" for intelligent beings from Mars. In 1898, H. G. Wells wrote "The War of the Worlds", a famous novel about Martians attacking the Earth. In 1938, Orson Welles broadcast a radio version of this story in the United States, and many people thought it was really happening and were very afraid. Beginning in 1912, Edgar Rice Burroughs wrote several novels about adventures on Mars. |
Mac OS | "For the Apple computer family, see macOS"
The Macintosh Operating System (Mac OS) is a program that allows a Macintosh computer to operate and be used. Mac OS was first made by Apple Inc. in 1984. In those days Mac OS was called Macintosh System Software – which was shortened to System or SSW (System Software). The term "Mac OS" first appeared in the splash screen for System 7.5.1, but was not adopted as the new name until the release of Mac OS 7.6.
The latest version of Mac OS is Mac OS 11 Big Sur. |
Apple Macintosh | The Apple Macintosh or just “Mac” is a line of personal computers made by the American company Apple Inc. The Macintosh was one of the first computers in which the people could use a mouse for pointing on a screen which had icons. This new way of working with a computer (interface) was known as graphical user interface. It was this feature of the Macintosh that made it so popular.
The Apple–Intel transition was when Apple changed the CPU of Macintosh computers from PowerPC processors to Intel x86 processors. It was announced at the 2005 World Wide Developers Conference. Steve Jobs announced it.
Macintoshes were different than other personal computers for many years based on their central processor unit (CPU). At the start, Macs used Motorola 68000 chips instead of Intel chips. Later, Macs used PowerPC chips. In 2006, Macs started to use Intel chips. Today, Macs are sold with Intel quad-core i7 chips.
The Mac does not have the Windows operating system installed on it. It has its own range of operating systems, known as macOS. The newest operating system is known as “Catalina". Macs can run both Windows and macOS at the same time with help of a program called “Boot Camp”, which comes on every Mac.
In general, Macintosh computers cost more than other computers of the same speed. |
Metre | A metre (US spelling, "meter") is the basic unit of length in the SI measurement system. The symbol for the metre is m. The first meaning (in the French Revolution) was one ten-millionth of the distance between the Earth's equator and the North Pole along the Paris meridian. The metre is now defined as the distance light travels in a vacuum in 1/299,792,458 of a second.
In the imperial system of measurement, one yard is 0.9144 metres (after international agreement in 1959), so a metre is very close to 39.37 inches: about 3.281 feet, or 1.0936 yards.
"*Note: units in bold are the most commonly used."
https://www.youtube.com/channel/UCLjFezysfbVZFZ_jeLB0iHg |
Magnifying glass | A magnifying glass is a lens through which can be used to make things appear bigger, so you can see them better. It is used in many applications and manual operations, e.g., for examining postage stamps in philately.
The magnifying glass consists of a piece of convex-shaped glass or plastic. It has to be held at the right distance between the eye and the object for the object to be in focus. The magnifying glass usually comes with a handle. A telescope is a more advanced kind of magnifying glass and consists of at least two glass lenses.
A pair of binoculars is like a telescope for each eye. "Spectacles" or eyeglasses also use lenses to correct a person's vision. |
Molecule | A molecule is the smallest amount of a chemical substance that can exist. If a molecule were split into smaller pieces, it would be a different substance.
Molecules are made up of atoms that are stuck together in a particular shape or form. Not all combinations of atoms are equally possible; atoms make certain shapes in preference to others. Also, they have different valency. For example, oxygen atoms always have two bonds with other atoms, carbon atoms always have four bonds with other atoms, and nitrogen atoms always have three bonds with other atoms.
In the kinetic theory of gases, the term "molecule" is often used for any gaseous particle regardless of its composition. According to this definition, noble gas atoms are considered molecules as they are in fact monoatomic molecules.
In gases like air, the molecules are just flying around. In liquids like water, the molecules are stuck together but they can still move. In solids like sugar, the molecules can only vibrate. In the fourth state of matter known as plasma, the atoms are ionized and cannot form molecules.
With a molecular formula, you can write down the numbers of all atoms in a molecule. For example, the molecular formula of glucose is CHO. That means that one molecule of glucose is made up of six carbon atoms, twelve hydrogen atoms and six oxygen atoms.
For a molecule to exist, atoms have to stick together. This happens when two atoms share electrons. Instead of circling just one atom, the electron now circles around two. This is called a covalent bond. Sometimes, more than one electron is shared. The more electrons are shared, the stronger the bond gets and the stronger the atoms stick together.
Bonds can also be broken apart. Since most bonds require energy to form, they also give off energy when they are broken. But before most bonds break, the molecule has to be heated. Then the atoms start to move, and when they move too much, the bond breaks. Molecules that require less energy to break than they give off when broken are called fuels. For example, a candle will just sit there and nothing happens. But when you use a match to light it, it will burn for a long time. The match brings the energy to break the first bonds, which release enough energy to break the bonds below them, until the candle has burned down.
There are also ionic bonds. |
Moral reasoning | Moral reasoning is a topic studied in psychology and in moral philosophy. It studies how people think about moral issues, problems, and questions. Psychologists who have studied it include Lawrence Kohlberg and Elliot Turiel. Kohlberg said that moral understanding develops in three main stages as a person gets older, but Turiel said that there are three domains of moral understanding that develop at the same time as a person gets older.
Moral philosophy, or ethics, is a major branch of philosophy. It is the study of value or quality. It covers the analysis and use of concepts such as right, wrong, good, evil, and responsibility. |
Mosque | A mosque is a place where Muslims worship. The word "mosque" comes from the Arabic word "masjid". A larger, 'collective', mosque is called a "masjid jāmi". Larger mosques offer more services to their community.
For many Muslim people, a mosque is more than a place of worship. Muslims worship, study and discuss Islam, and do many other things in a mosque and its compounds. In the United Kingdom, many mosques are used as community centres. They are also used to teach about Islam. Religious festivals and gatherings are held in mosques. Weddings are one example. Mosques have rules to control what people do inside. One of these is that it is disrespectful to disturb another person who is worshipping.
Many mosques are known for their Islamic architecture. The earliest mosques, opened in 7th century were open-air spaces. They are the "Quba Mosque" and "Masjid al-Nabawi". Later Mosques were buildings that were specially designed. Nowadays, mosques are in every continent, except Antarctica.
Many mosques are famous works of architecture. They are often built in a style that has stayed the same for many centuries. Many mosques have prayer halls, domes, and minarets. They may also have a courtyard. Mosques are often built with patterned walls.
Mosques were first built on the Arabian Peninsula. The Muslims who built them used old architectural styles. They also combined these styles in new ways. A major influence was the palaces built during the Parthian and Sassanid dynasties of Persia. The "Sarvestan palace" from the Sassanid era is a good example of this. It has an arched entrance and a central dome. These features already existed in Persia before Islam.
After the Arab invasion of Persia, the new style, with its Sassanid influence, was used for the new Islamic world. Many forms of mosques have developed in different regions of the Islamic world. Important mosque types include the early Abbasid mosques, T-type mosques, and the central-dome mosques of Anatolia. In the 20th century, many countries that grew rich from oil paid for the building of many new mosques. The rulers of these countries often hired leading architects to design these mosques. They included non-Muslims.
Many early mosques have a square or rectangular plan. They also have a prayer hall and an enclosed courtyard. This is known as "Arab-plan". The first mosques of this type were built during the Umayyad Dynasty.
The flat roof of the prayer hall was supported by columns. Many rows of columns were needed to support such roofs; this is called "hypostyle architecture". One of the most famous hypostyle mosques is the Mezquita de Córdoba in Spain. It is supported by over 850 columns.
In the warm Mediterranean and Middle Eastern climates, the courtyard served to hold the large number of worshippers during Friday prayers. Often, hypostyle mosques have outer arcades. They allow the visitors to enjoy the shade. Arab-plan mosques were built mostly during the Umayyad and Abbasid dynasties. The Arab plan was very simple, which did not allow for much further development. This caused that style of mosque to fall out of favour.
The Ottomans began building "central dome mosques" in the fifteenth century. These mosques have a large dome centered over the prayer hall. There may also be smaller domes, which are off-center over the prayer hall or the rest of the mosque. This style was heavily influenced by the Byzantine religious architecture with its use of central domes.
"Iwan mosques" are famous for their domed rooms and "iwans". Iwans are spaces with an arched roof. They have an opening at one end. One or more iwans face a central courtyard that serves as the prayer hall. The style borrows from pre-Islamic Iranian architecture. Most mosques with this style are in Iran.
Most mosques have minarets. Minarets are tall towers. Usually they are at one of the corners of the mosque. The top of the minaret is the highest point in the mosque, and usually the highest point in the area around the mosque. The tallest minaret in the world is in the Hassan II Mosque in Casablanca, Morocco.
The first mosques had no minarets. The most conservative Islamic groups, like "Wahhabis", still avoid building minarets. They see them as simply a fancy decoration and unnecessary. The first minaret was built in 665 in Basra during the reign of the Umayyad caliph Muawiyah I. Muawiyah encouraged the building of minarets, as they were supposed to be the same as bell towers on Christian churches. Because of this, mosque architects used the shape of the bell tower for their minarets. Both the minaret and the bell tower serve the same purpose — to call the faithful to prayer.
Before the five required daily prayers, a "muezzin" calls the worshippers to prayer from the minaret. In many countries like Singapore where Muslims are not the majority, mosques are stopped from loudly playing the call to prayer. The main problem is the use of electronic amplification of the call, which is now widely used by mosques.
The domes were often placed directly above the main prayer hall. They represent the universe that Allah created. At first, these domes were small. They only took up a small part of the roof near the "mihrab". Later, they took the whole roof above the prayer hall.
Domes normally have the shape of a hemisphere. The Mughals in India popularized onion-shaped domes in South Asia and Persia. Some mosques have several domes, as well as the main large dome. The other domes are often smaller.
Domes would help the "imam" be heard, as the sound waves would bounce in and then out of the dome making the voice louder.
All mosques have a prayer hall, which is also called "musalla". Normally, there is no furniture in it except for prayer mats or rugs. These are necessary, as Islamic prayer is usually done kneeling.
Some mosques have Arabic calligraphy and "Qur'anic" verses on the walls to help worshipers focus on the beauty of Islam and its holiest book, the "Qur'an", as well as for decoration.
The "qiblah wall" is usually at the other side of the entrance to the prayer hall. This wall is specially decorated. In a properly sited mosque, it will be set perpendicular to a line leading to Mecca. People pray in rows parallel to the "qiblah" wall. They arrange themselves so they face Mecca. In the "qiblah" wall, usually at its center, is the "mihrab", a niche or depression showing the direction of Mecca. The "mihrab" serves as the place where the imam leads the five daily prayers.
All people must wash themselves before they pray. Mosques often have fountains or other facilities for washing in their entrances or courtyards, so that people can perform the washing ritual before prayer.
At very small mosques, worshippers may use restrooms for their ritual washing, or wu'du. In traditional mosques, there is often a building specially for washing. This is often in the center of the courtyard. In the prayer halls, people must not wear shoes for much the same reason.
Modern mosques should appeal to the community they serve. For this reason, other facilities may also be available at the mosque, like health clinics, libraries, and sports halls.
There may be decorative tiles, plaster or coloured mosaics on the walls. There are no pictures or statues.
Adult Muslims are expected to pray five times a day. Most mosques have formal prayers for each of these times. If performing the prayer is difficult, for example for ill people, then exceptions are made.
Mosques also hold a special prayer service, called "jumuah". This is done once a week. It is a form of Sabbath and replaces the Friday prayers at the mosque. Daily prayers can be done anywhere. However, Muslims are expected to do their Friday prayer at the mosque.
When a Muslim dies, a funeral prayer is normally held. It is held outdoors in a courtyard or square close to the mosque. The prayers have all the worshippers present, including the imam, taking part. During eclipses, mosques will host special prayers called eclipse prayers.
There are two large holidays ("Eids") in the Islamic calendar. During these days, there are special prayers at mosques in the morning. Larger mosques will normally hold them for their own communities as well as the people from smaller local mosques. Mosques, especially those in countries where Muslims are the majority, will also host "Eid" prayers outside in courtyards or town squares.
There are many events in "Ramadan", Islam's holiest month. During "Ramadan", Muslims must fast during the day. Mosques organise "iftar" dinners after sunset. These are done after the fourth required prayer of the day. Part of the food is given by members of the community, which creates nightly potluck dinners. The community contribution to these dinners is required. For this reason, mosques with smaller communities may not be able to hold the "iftar" dinners daily.
Some mosques will also hold meals in the morning before dawn. Mosques will often invite poorer members of the community to these meals. Islam sees giving charity during Ramadan as good acts.
Larger mosques sometimes offer special, optional prayers. They are done after the last required prayer of the day. During each night of prayers, one member of the community who has memorized the entire Qur’an will recite a part of the book. It can last for up to two hours. Sometimes, several such people (not necessarily of the local community) take turns to do this. During the last ten days of Ramadan, larger mosques will host all-night programs to observe "Laylat al-Qadr". It is the night Muslims believe that the Islamic prophet Muhammad first received Qur'anic revelations. On that night, between sunset and sunrise, mosques employ speakers to teach the worshipers about Islam. Mosques or the community usually provide meals at times through the night.
During the late twentieth century, more and more mosques have been used for political purposes. Modern-day mosques in the Western world want to educate good citizens. The details differ greatly from mosque to mosque and from country to country.
Countries with small Muslim populations use mosques as a way to support civic participation. They are more likely to do this than Muslim-majority countries of the Greater Middle East. American mosques host voter registration and civic participation drives. In the United States, Muslims are often immigrants, or the children of immigrants. Mosques want to interest these people for politics. They also want to keep them informed about issues that concern the Muslim community. People who attend the services at the mosque regularly are more likely to take part in protests, to sign petitions, and to involve themselves in political matters.
A link between political views and mosque attendance can still be seen in other parts of the world. After the al-Askari Mosque bombing in February 2006, imams and other Islamic leaders used mosques and Friday prayers to call for calm and peace during the widespread violence.
Beginning in the late twentieth century and continuing into the early twenty-first century, a small number of mosques have also become a base for extremist imams to support terrorism and extreme Islamic ideals. Finsbury Park Mosque in London is a mosque that has been used in this manner.
Like other places of worship, mosques can be at the center of social conflicts.
Babri Mosque was the centre of such a conflict up until the early 1990s when it was demolished. Before a solution could be found, the mosque was destroyed by about 200,000 Hindus. It took place on 6 December 1992. The mosque was built by Babur to mark the birthplace of Ram. It was believed to be on a site of an earlier Hindu temple. The conflict over the mosque was directly linked to rioting in Bombay (present-day Mumbai) as well as bombings in 1993 that killed 257 people.
In February 2006, a bombing seriously damaged Iraq's al-Askari Mosque. This increased the existing tensions. The conflict between two Muslim groups in Iraq had already led to other bombings. However mosque bombings are not limited to Iraq. In June 2005, a suicide bomber killed at least 19 people at an Afghan mosque. In April 2006, there were two explosions at India's Jama Masjid.
After the September 11 attacks, several American mosques were targets of attacks. These ranged from simple vandalism to arson.
The Jewish Defense League was suspected of plotting to bomb the King Fahd Mosque in Culver City, California. There were similar attacks in the United Kingdom after the 7 July 2005 London bombings. Outside the Western world, in June 2001, the Hassan Bek Mosque was the target of attacks. The attacks involved hundreds of Israelis angry at Arabs for a previous attack.
Saudi involvement in building mosques around the world only goes back to the 1960s.
In the 1980s, the Saudi Arabian government began to pay for the building of mosques in countries around the world. An estimated US$45 billion has been spent by the Saudi Arabian government for mosques and Islamic schools in foreign countries. "Ain al-Yaqeen", a Saudi newspaper, reported in 2002 that Saudi money may have helped to build as many as 1,500 mosques and 2,000 other Islamic centers. Saudi citizens have also given a lot of money to mosques in the Islamic world, especially in countries where they see Muslims as poor and oppressed. Following the fall of the Soviet Union, in 1992, mosques in Afghanistan received money from Saudi citizens. The King Fahd Mosque in Culver City, California and the Islamic Cultural Center of Italy in Rome are two of Saudi Arabia's largest investments in foreign mosques as former Saudi king Fahd bin Abdul Aziz al-Saud gave US$8 million and US$50 million to the two mosques, respectively.
In a mosque, people should keep focused on worshiping "Allah". For this reason, there are a number of rules about the correct behaviour in a mosque. Some of these rules are the same all over the world, such as no shoes should be worn in the prayer hall. Other rules are different from mosque to mosque.
It is generally seen as good to have someone who leads the prayers, though this is not strictly necessary. The person who usually leads the prayers is called "imam". He must be a free and honest man. He should also be an authority when it comes to answering questions on religion. In mosques that were built or that are kept up by the government, the imam is selected by the ruler. In private mosques, the community selects the imam, through majority voting.
Only men may lead prayers for men. Women are allowed to lead prayers for congregations where there are only women.
In addition to washing, there are other rules that also apply to those who enter the mosque, even if they do not wish to pray there. It is forbidden to wear shoes in the carpeted area of the prayer hall. Some mosques also do not allow wearing shoes in other parts, even though these may not be devoted to praying.
Islam requires that its believers wear clothes that show modesty. As a result, both men and women must follow this rule when they attend a mosque (though mosques may not always enforce the rules). Men are supposed to come to the mosque wearing loose and clean clothes that do not show the shape of the body. Similarly, women who come to the mosque are expected to wear loose clothing, shirts, pants that cover to the wrists and ankles and cover their heads such as with a hijab. Many Muslims, regardless of their ethnic background, wear Middle eastern clothing associated with Arabic Islam to special occasions and prayers at mosques.
Mosques are places of worship. For this reason, those inside the mosque should be respectful to those who are praying. Loud talking or discussion of topics that could be disrespectful, is forbidden in areas where people are praying. It is also considered as rude to walk in front of Muslims in prayer or otherwise disturb them.
Islamic law requires men and women to be separated in the prayer hall. Ideally, women should pray behind men. The second caliph Umar at one time stopped women from attending mosques, especially at night, because he feared they may be teased by males, so he made them to pray at home. Sometimes a special part of the mosque was railed off for women; for example, the governor of Mecca in 870 had ropes tied between the columns to make a separate place for women.
Many mosques today will put the women behind a barrier or partition or in another room. Mosques in South and Southeast Asia put men and women in separate rooms, as the divisions were built into them centuries ago. In nearly two-thirds of American mosques, women pray behind partitions or in separate areas, not in the main prayer hall; some mosques do not admit women at all. Although there are sections only for women and children, the Grand Mosque in Mecca is desegregated.
A few scholars of Islamic law believe that non-Muslims may be allowed into mosques, as long as they do not sleep or eat there. Followers of the "Maliki" school of Islamic jurisprudence disagree. They say that non-Muslims may not be allowed into mosques at all.
Different countries have different opinions on the question. Nearly all the mosques in the Arabian Peninsula as well as Morocco do not allow non-Muslims. The Hassan II Mosque in Casablanca is one of only two mosques in Morocco currently open to non-Muslims.
In modern-day Saudi Arabia, the Grand Mosque and all of Mecca are open only to Muslims. Likewise, the Masjid al-Nabawi and the city of Medina that surrounds it are also off-limits to those who do not practice Islam. For mosques in other areas, it has most commonly been taken that non-Muslims may only enter mosques if granted permission to do so by Muslims and if they have a proper reason.
In modern Turkey non-Muslim tourists are allowed to enter any mosque, but must obey the rules of decorum. Visiting a mosque is allowed only between prayers; visitors must wear long trousers and take off their shoes; women must cover their heads; no photos; no loud talk is allowed. No references to other religions are allowed (no crosses on necklaces, no cross gestures etc.).
However, there are also many other places in the west as well as the Islamic world where non-Muslims are welcome to enter mosques. Most mosques in the United States, for example, report receiving non-Muslim visitors every month. Many Mosques throughout the United States welcome non-Muslims as a sign of openness to the rest of the community and to encourage conversions to Islam.
Dogs are usually banned from entering mosques, but on 24 September 2008, the Muslim Law Council UK made special ruling, called a "fatwa", which granted a blind Muslim permission to take his guide dog into the mosque.
It is common for a smaller mosque to serve as a hostel for Muslims on "haj" (pilgrimage to Mecca). Sometimes mosques are used for refugees, or as temporary homes for homeless people. Obligations to neighbours in Islam are very strict, and specific. In the Qur'an Mohammed(pbuh) said that a person who helps others in the hour of need, and who helps the oppressed; that person God will help on the Day of Travail (agony). There are other commands, such as helping the poor and being nice to people. An important part of being Muslim, or just being part of the mosque, is taking care of people who need help. A mosque is a social, as well as a religious, group.
A madrassa is a little different from a mosque. A madrassa focuses on teaching Islam, usually to children and young people.
When Spain was under Muslim control, some of the most beautiful buildings were mosques. After 1491, Spain was under Christian control. However, the Christians did not tear down the mosques. They simply put a crucifix in them to make them into churches. These mosques influenced the Renaissance architecture (way of building) in Europe. |
Mammal | The class Mammalia are a group of vertebrate animals. They have fur or hair and a very precise kind of temperature regulation.
With the exception of the monotremes, all mammals bear live young. Unlike other vertebrates, they are the only animals that produce milk for the young through their mammary glands. Parental care of the young is universal among mammals, sometimes for extended periods.
Most marsupial and eutherian mammals have a reproductive cycle known as the oestrous cycle (U.S: estrous cycle). Females are sexually active only during the oestrous stage, when they are 'on heat' for a few days each month. If an ovum is not fertilized, the endometrium (uterus lining) is resorbed. Oestrus cycles may occur once or twice a year, or many times a year. Each group of mammals has its own frequency.
Humans and primates, are quite different. They have a menstrual cycle. In this case, females are sexually receptive at any time, but only fertile when an ovum is released from an ovary. In this case, the endometrium (if not needed for an fertilised egg) is discarded. The endometrium is shed, and takes with it a certain amount of blood. In this system, eggs are released from the ovaries mostly in the middle of the cycle, away from the menstrual period. This ovulation is 'concealed', meaning, it is not obvious when it occurs. This process, so it is thought, tends to keep the male and female together, which is unusual in mammals with the oestrous cycle.
One diagnostic feature is the lower jaw which, unlike earlier forms, is composed of a single bone, the dentary. This is one feature which can be seen in fossils, or at least those which are complete enough to have the lower jaw. Mammals have three little bones in their inner ear, the ear ossicles. The ear ossicles are bones which were, long ago, part of the lower jaw in early proto-mammals.
There are quite a number of other features, particularly in the skull and limbs, so that it is usually possible to identify and describe a mammal from its skeleton alone.
Another diagnostic feature is the neocortex of the brain, which no other vertebrate has. This is involved in the kind of flexible behavior and learning typical of mammals. Reptiles and birds have much of their behavior controlled by "inherited behavior chains", which roughly translates as "instincts". Almost all animals can do some learning, but mammals do far more than other vertebrates. Their behavior is much more flexible than lizards, for example, and that is made possible by their neocortex.
Other things in the life of mammals seem to be connected with this flexibility and learning. Play is a kind of early learning period in which, according to one theory, mammals develop skills which they will need in life. All mammalian young play, and this is very obvious in the more intelligent mammals (primates, cats).
The emotions of mammals are very noticeable, and rather similar to ours. It is possible, and quite common, for humans to have a friendly relationship with another mammal. It is quite impossible for a human to have any kind of relationship with a snake or a gecko (for example). This is because the reptile simply does not have the same basic emotions as a human.
There are about 50 characters which are typical of mammals, and some of the most important are discussed above. A few more examples will make it clear that mammals are very different from reptiles and birds:
In the language of cladistics, these 50 unique characters are apomorphies which prove that mammals are a clade descended from a common ancestor.
All mammals feed milk to their young, and protect and look after them.
The vast majority of mammal species give birth to live young, these are the placental mammals, most of which are classified as Eutheria and a small number are classified as marsupials.
Marsupials are mammals with pouches to carry young in, like the kangaroo.
There are only five species (the monotreme mammals) that lay eggs, the duck-billed platypus "Ornithorhynchus", and four species of spiny anteater "Echidna". The monotremes are confined to Australia and New Guinea, and are the sole survivors of an earlier group of mammals.
In terms of number of species mammals, with 5488 species, are not the most successful vertebrates. Birds, with about 10,000 species have nearly twice as many, and reptiles have just as many as birds. Fish have even more species. There are 27,000 species of fish, of which nearly 26,000 are bony fish.
Despite this, many zoologists do regard mammals as a successful group of animals. One reason is that they are successful in all habitats on Earth. In the air, in the water, in forests, in the colder regions of the world, and above all on grasslands, where they are outstandingly successful.
In the air, the bats (Chiroptera) are the mammalian order with the most species. They 'own' the nighttime, since birds are largely diurnal (daytime) animals. Bats are hugely successful, mostly as nighttime predators of insects.
Seagoing mammals, the Cetacea and the pinnipeds, are very successful and significant predators. This includes the whales, seals, walrus, dolphins and others.
The terrestrial mammals are fewer in number of species than lizards, but they are huge in individual numbers, and far more important in the life of the terrestrial biomes. Their ability to move from place to place and adapt has made them a most effective group. Many mammals live in cold places. These mammals have thick hair or blubber to keep them warm. Others may live in rainforests. On land the rodents (rats, mice) are hugely successful, more common in numbers than any other mammals. Large mammals on land have been hunted to extinction in some parts of the world, but the ones which remain are now better protected.
Last, but certainly not least, are the primates. Their natural habitat, with few exceptions, are the forests. Most live in the trees, with hands that grasp, good colour vision, and intelligence. In the Pliocene period some moved out onto the savannahs as grassland replaced forests. Mankind is the result of this shift into the savannahs.
The evolutionary relationships among land vertebrates is as follows:
This sort of classification is not traditional, but it does reflect our knowledge of palaeontology and evolution.
A somewhat standardized classification system has been adopted by most current mammalogy classroom textbooks. It is based on living animals. The following taxonomy of extant and recently extinct mammals is from Vaughan et al. 2000. |
Class Mammalia | Mammals can be divided in a number of orders:
Because two quite different dates are given in the taxobox, an explanation is needed. Rowe defines mammals as "the taxon originating with the most recent common ancestor of extant [living] Monotremata and Theria". That puts the emphasis heavily on living mammals, where, as Rowe points out, the database of characters is extensive.
Kemp explains the problem with that approach: "If the definition of a mammal is based rigorously upon possession of all the characters of living mammals, then some fossil forms that are extremely mammalian in anatomy... are excluded".
"An altogether different perspective on defining Mammalia is based on traditional palaeobiological practice. An arbitrary decision is made about which characters to select as defining characters... Characters deemed appropriate are those reflecting the... fundamental mammalian biology. The essence of mammalian life is to be found in their endothermic temperature physiology, greatly enlarged brain, dentition capable of chewing food, highly agile, energetic locomotion, and so on. The organisms that achieved this grade of overall organisation are deemed to be Mammalia... Around the end of the Triassic period, about 205 mya, a number of fossils are found of very small animals that have [most] of the skeletal characters of modern mammals".
This difference in outlook explains the difference in the two dates given in the taxobox.
Number
A number is a concept from mathematics, used to count or measure. Depending on the field of mathematics, where numbers are used, there are different definitions:
Numbers are also used for other things like counting. Numbers are used when things are measured. Numbers are used to study how the world works. Mathematics is a way to use numbers to learn about the world and make things. The study of the rules of the natural world is called science. The work that uses numbers to make things is called engineering.
There are different ways of giving symbols to numbers. These methods are called number systems. The most common number system that people use is the "base ten" number system. The "base ten" number system is also called the decimal number system. The base ten number system is common because people have ten fingers and ten toes. There are 10 different symbols {0, 1, 2, 3, 4, 5, 6, 7, 8, and 9} used in the base ten number system. These ten symbols are called digits.
A symbol for a number is made up of these ten digits. The position of the digits shows how big the number is. For example, the number 23 in the decimal number system really means (2 times 10) plus 3. Similarly, 101 means 1 times a hundred (=100) plus 0 times 10 (=0) plus 1 times 1 (=1).
Another number system is more common for machines. The machine number system is called the "binary" number system. The binary number system is also called the base two number system. There are two different symbols (0 and 1) used in the base two number system. These two symbols are called bits.
A symbol for a binary number is made up of these two bit symbols. The position of the bit symbols shows how big the number is. For example, the number 10 in the binary number system really means 1 times 2 plus 0, and 101 means 1 times four (=4) plus 0 times two (=0) plus 1 times 1 (=1). The binary number 10 is the same as the decimal number 2. The binary number 101 is the same as the decimal number 5.
English has special names for some of the numbers in the decimal number system that are "powers of ten". All of these power of ten numbers in the decimal number system use just the symbol "1" and the symbol "0". For example, ten tens is the same as ten times ten, or one hundred. In symbols, this is "10 × 10 = 100". Also, ten hundreds is the same as ten times one hundred, or one thousand. In symbols, this is "10 × 100 = 10 × 10 × 10 = 1000". Some other powers of ten also have special names:
When dealing with larger numbers than this, there are two different ways of naming the numbers in English. Under the "long scale", a new name is given every time the number is a million times larger than the last named number. It is also called the "British Standard". This scale used to be common in Britain, but is not often used in English-speaking countries today. It is still used in some other European nations.
Another scale is the "short scale", under which a new name is given every time a number is a thousand times larger than the last named number. This scale is a lot more common in most English-speaking nations today.
Natural numbers are the numbers which we normally use for counting: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, etc. Some people say that 0 is a natural number, too. The set of all natural numbers is written as formula_1.
Another name for these numbers is positive numbers. These numbers are sometimes written as +1 to show that they are different from the negative numbers. But not all positive numbers are natural (for example, formula_2 is positive, but not natural).
If 0 is called a natural number, then the natural numbers are the same as the whole numbers. If 0 is not called a natural number, then the natural numbers are the same as the counting numbers. So if the words "natural numbers" are not used, then there will be less confusion about whether zero is included or not. But unfortunately, some say that zero is not a whole number, while others say that whole numbers can be negative. "Positive integers" and "non-negative integers" are another way to include zero or exclude zero, but only if people know those words.
Negative numbers are numbers less than zero.
One way to think of negative numbers is to use a "number line". We call one point on this line zero. Then we will label (write the name of) every position on the line by how far to the right of the zero point is. For example, the point one is one centimeter to the right, and the point two is two centimeters to the right.
However, the point one centimeter to the left of the zero point cannot be point one, since there is already a point called one. We therefore call this point minus one (−1, as it is one centimeter away but in the opposite direction).
A drawing of a number line is below.
All the normal operations of mathematics can be done with negative numbers:
Since finding the square root of a negative number is impossible for real numbers (as negative times negative equals positive for real numbers), the square root of -1 is given a special name: "i". This is also called the imaginary unit.
Integers are all the natural numbers, all their opposites, and the number zero. Decimal numbers and fractions are not integers.
Rational numbers are numbers which can be written as fractions. This means that they can be written as "a" divided by "b", where the numbers "a" and "b" are integers, and "b" is not zero.
Some rational numbers, such as 1/10, need a finite number of digits after the decimal point to write them in decimal form. The number one tenth is written in decimal form as 0.1. Numbers written with a finite decimal form are rational. Some rational numbers, such as 1/11, need an infinite number of digits after the decimal point to write them in decimal form. There is a repeating pattern to the digits following the decimal point. The number one eleventh is written in decimal form as 0.0909090909 ... .
A percentage could be called a rational number, because a percentage like 7% can be written as the fraction 7/100. It can also be written as the decimal 0.07. Sometimes, a ratio is considered as a rational number.
Irrational numbers are numbers which cannot be written as a fraction, but do not have imaginary parts (explained later).
Irrational numbers often occur in geometry. For example, if we have a square which has sides of 1 meter, the distance between opposite corners is the square root of two, which equals 1.414213 ... . This is an irrational number. Mathematicians have proved that the square root of every natural number is either an integer or an irrational number.
One well-known irrational number is pi. This is the circumference (distance around) of a circle divided by its diameter (distance across). This number is the same for every circle. The number pi is approximately 3.1415926535 ... .
An irrational number cannot be fully written down in decimal form. It would have an infinite number of digits after the decimal point, and unlike 0.333333 ..., these digits would not repeat forever.
Real numbers is a name for all the sets of numbers listed above:
The real numbers form the real line. This is all the numbers that do not involve imaginary numbers.
Imaginary numbers are formed by real numbers multiplied by the number i. This number is the square root of minus one (−1).
There is no number in the real numbers which when squared, makes the number −1. Therefore, mathematicians invented a number. They called this number i, or the imaginary unit.
Imaginary numbers operate under the same rules as real numbers:
Imaginary numbers were called "imaginary" because when they were first found, many mathematicians did not think they existed. The person who "discovered" imaginary numbers was Gerolamo Cardano in the 1500s. The first to use the words "imaginary number" was René Descartes. The first people to use these numbers were Leonard Euler and Carl Friedrich Gauss. Both lived in the 18th century.
Complex numbers are numbers which have two parts; a "real" part and an "imaginary" part. Every type of number written above is also a complex number.
Complex numbers are a more general form of numbers. The complex numbers can be drawn on a number plane. This is composed of a real number line, and an imaginary number line.
All of normal mathematics can be done with complex numbers:
To multiply two complex numbers is more complicated. It is easiest to describe in general terms, with two complex numbers a + bi and c + di.
formula_3
For example, (4 + 5i) × (3 + 2i) = (4 × 3 − 5 × 2) + (4 × 2 + 5 × 3)i = (12 − 10) + (8 + 15)i = 2 + 23i.
A real or complex number is called a "transcendental number" if it can not be obtained as a result of an algebraic equation with integer coefficients.
formula_4
Proving that a certain number is transcendental can be extremely difficult. Each transcendental number is also an irrational number. The first people to see that there were transcendental numbers were Gottfried Wilhelm Leibniz and Leonhard Euler. The first to actually prove there were transcendental numbers was Joseph Liouville. He did this in 1844.
Some well-known transcendental numbers include: |
November | November (Nov.) is the eleventh and penultimate (second-last) month of the year in the Gregorian calendar, coming between October and December. It has 30 days. Its name is from the Latin word "novem", which meant "nine". It was the ninth month of the year before January and February were added to the Roman Calendar.
November always begins on the same day of the week as March, and additionally, February in common years. November always ends on the same day of the week as August.
November is the eleventh month of the year in the Gregorian calendar, after October and before December, which is the last month. November has 30 days. It was the ninth month in the old Roman calendar, which is where its name comes from. It kept its name when January and February were added to the beginning of the year, despite becoming the eleventh month. The ninth month is now September.
November begins on the same day of the week as February in common years and March every year, as each other's first days are exactly 39 weeks (273 days) and 35 weeks (245 days) apart respectively. November ends on the same day of the week as August every year, as each other's last days are exactly 13 weeks (91 days) apart.
In common years, November starts on the same day of the week as June of the previous year, and in leap years, September and December of the previous year. In common years, November finishes on the same day of the week as March and June of the previous year, and in leap years, September of the previous year.
In years immediately before common years, November starts on the same day of the week as August of the following year, and in years immediately before leap years, May of the following year. In years immediately before common years, November finishes on the same day of the week as May of the following year, and in years immediately before leap years, February and October of the following year.
In the Northern Hemisphere, November is an Autumn (Fall) month, and the further north in the hemisphere, the more likely it is to get colder as December approaches. In the Southern Hemisphere it is a Spring month. In each hemisphere, it is the seasonal equivalent of May in the other.
Several observances around the beginning of the month are believed to be related, linked to the old Celtic celebration of Samhain on November 1. These events include Halloween (October 31), Day of the Dead in Mexico (October 31 to November 2), All Saints Day (November 1) and All Souls Day (November 2).
In several mainly Christian countries, it is month in which people who died in war are commonly remembered, mainly related to the end of World War I on November 11, 1918. Near the end of the month Advent, the period leading up to Christmas, begins. |
National anthem | A national anthem is a country's official national song that the people of a country use to remember and respect their country.
Some countries, like Spain, have a national anthem which has no lyrics (words of a song) |
Name | A name is a word (or a set of words) given to things and people.
For example, "cat" is the name of a kind of animal. "Ryan" is a name of a person, usually a male. "Julia" is a common female name.
The word 'name' can also be used as a verb. To name something is to give it a name.
In many cultures, there are rules and customs about how to give a person a name.
Some of the rules are defined by laws, and others are defined by traditions (doing things in the way they have been done for a long time).
There are rules about different aspects of the names and naming, including the following:
1. Number of parts of a name
In some cultures, a person has a one-part name, such as "ShiningWater."
In other cultures, a person has a two-part name, such as "John Smith."
In some cultures, a person can have any number of name parts. In the United States, for example, some people have three: first name, middle name, and last name. Other people have only two: a first and last name.
In Chinese cultures, it is typical for a person to have three-part name, such as "Cheah Ching San," where "Cheah" is the surname. Written in English format a comma is introduced making it "Ching San, Cheah."
2. Relations with names of parents and other relatives
In some cultures, people have the same "family name" (or surname) as their parents. For example, the father of John Smith may be Mike Smith. And Mike Smith's father may be James Smith. The "Smith" part is the same for all the family.
In other cultures, a person has the same name as his or her father, but the name is in a different place. For example, Shafiq Hanif's son may be Hanif Kamal. Hanif is in both the father's and son's name.
3. Name changes
In some cultures, a name changes when people marry, divorce, go through some religious ceremony, etc. For example, in some Spanish-speaking countries, people use two last names: their mother's father's name and their father's name. If Elena Rodriguez Gomez and Jose Sanchez Soria marry, she may change her name to Elena Rodriguez de Sanchez, and their child could be named Pilar Sanchez Rodriguez, taking the names of both of her grandfathers.
4. Name origins
In some cultures, personal names come from history. In most European countries, some first names are taken from the Bible. In some cultures, names are taken from a relative. In other cultures, a name shows what the parents hope their child will be like. A baby may be given a name Wisdom because parents hope the baby will be a wise girl or boy.
Some cultures avoid giving people a name of an animal. For example, there is no name like dog, cat, snake, owl, or fish in Japanese people's first names. But in some cultures animal names may be good.
5. Lengths, pronunciations, spelling, etc.
In some languages and cultures, you can tell if a word is a person's name or not by just looking at the spelling or listening to its pronunciation. There are some other linguistic patterns. For example, many Chinese names are made up of three syllables.
6. Use of names, titles, nicknames, etc.
In some cultures, people use names when they call each other. In other cultures, people use their nicknames. In some other cultures, people use their titles ("father," "professor," etc.) when they call each other.
7. Spelling of names, titles, nicknames, etc.
8. Name awareness
Taking note of names is taken a step farther by those who elect to celebrate a name (e.g., "Celebrate Your Name Week") whether their own name, someone else's name, or names in general, complete ownership of one's name might very well include celebrating it.
9. Middle names
While some people might choose to "hide" a middle name for any number of reasons (i.e., they consider the middle name they were given to be an "embarrassment"), others have taken to celebrating their middle name (e.g., "Middle Name Pride Day").
In the English language, names exclusively are usually pronounced in correlation with the spelling, however can be pronounced as desired, e.g. John is (jon) but can also be (ned). However, not probable, is held true in the English rules of grammar. |
Examples of names | Sarah, Lucy, Ellen, Claire, Ben.
Names can be shortened e.g. Isabelle can become Izzy or Belle.
Here are some things that are often found in Japanese names today. In the past, people went by different rules.
1. Number of parts of a name
Japanese names have two parts. One is the family name and the other is the given name.
"Suzuki Ichiro" is a name of a Japanese person. Suzuki is the family name, and Ichiro is the first name. In the Japanese language, the family name comes first, and the given name comes second. (It is like writing Smith John, instead of John Smith.)
Only some members of the royal family do not have a family name.
2. Relations with names of parents and other relatives
A newborn baby gets a family name from their parents. The parents have the same family name. So, a son of Ono Yoko (female) and Ono Ken (male) is Ono something.
The family name Ono is mostly shared by the paternal (male) part of the family. So Ono Ken's parents have the family name Ono, but Ono Yoko's parents probably do not.
3. Name changes
Names of people change when they marry and divorce. It is a custom in many parts of the world that women change their family name to that of their new husband when they marry. However, in Europe and North America especially, many women no longer do this even though their mothers and grandmothers may have. Sometimes, the man will take the woman's family name.
4. Name origins
5. Lengths, pronunciations, spelling, etc.
6. Use of names, titles, nicknames, etc. |
Niihau | Niihau (or Niʻihau) is the smallest of the inhabited islands of Hawaii, in the United States. It has a land area of 70 sq. miles (184 km). It is the oldest of the eight main islands.
The whole island is owned by the Robinson family. They bought it from the Kingdom of Hawaii for $10,000. It was said that the buyer, Elizabeth Sinclair (later Sinclair-Robinson), liked the island better than other places such as Waikiki, Pearl Harbor, and the island of Lanai. There is a small US Navy base where a handful of Navy people work.
The island has a few hundred permanent inhabitants. Almost all of them are native Hawaiians. They support themselves largely with small family farms. Many work for the ranch owned by the Robinsons. The native Hawaiians lead a rural, low-tech life. They speak the Hawaiian language and keep traditions alive. This is because Ms. Sinclair promised to help preserve Hawaiian culture and tradition when she bought the island. Niihau is the only one of the Hawaiian islands where the Hawaiian language is the main language.
Niihau is also known as the "Forbidden Island". This is due to the fact that until recently, the island was off-limits to all but family members, US Navy personnel, government officials and expressly invited guests. Now, tourists can go on one of a limited number of supervised tours or hunting safaris.
On the beaches of the island are found shells which are the only shells to be classified as gems. Niihau shells and the jewelry made from them are very popular. Many, especially those with darker and richer color, are collectors items. The sale of shells and shell jewelry brings extra money for the local people. |
Nēnē | The Nēnē, or Hawaiian goose ("Branta sandvicensis") is a species of goose. It is found today on only three Hawaiian islands. It gets its name from its soft call.
This is an unmistakable species, with its generally brown plumage (feathers) and darker head. Its strong toes have much reduced webbing (skin between the toes), an adjustment to the lava flows on which it breeds. The Nēnē goes about on land much more than other water birds. When moulting (dropping old feathers and growing new ones), the Nēnē cannot fly, as do other geese, a factor which made it vulnerable to hunting.
The Nēnē was once among the most threatened waterfowl species around the world. Once common, hunting and predators brought to the islands such as mongooses, pigs and cats reduced the population to only 30 birds in the 1950s. However, this species breeds well in captivity (zoos and bird parks), and has been successfully re-introduced. There are also good numbers in wild bird collections.
The Nēnē is the state bird of Hawaii. |
Network | A communication network is a group of things that are connected or linked together. They may be used for talking or other communication to transfer information, data, signal and things as in a transport network. The pattern by which things are connected is called a network topology. A television network, for example, connects television stations. Computer networks are numerous. |
Fishing net | A fishing net is a woven trap usually used to catch fish. They are usually made out of rope. A net is a kind of tool. |
Internet slang | Internet slang is slang words which are used on the internet. Most of these words are new, such as Wiki and blog, which were not used before the internet became popular.
Some old words were given new meanings, such as mail (which now means email). This makes many metaphors on the Internet, such as boot (which otherwise mean a shoe) and link (which otherwise means a joint in a metal chain). Some existing acronyms, such as "AFK" (To mean "Away from keyboard") and "IRL" (To mean "In real life") were used on bulletin board systems before the internet became popular. These are now used on the internet, such as in chat rooms and on instant messenger software.
People have also created some verbs and adjectives to describe things that only happen on the internet:
Shorthand is where a word is written in a shorter way because it is quicker and easier to type. It is also done to fit more text into a limited space.
Internet slang uses many acronyms because they are quicker and easier to type. They are often shorthand for common phrases and idioms, but they can show somebody's emotions and their certainty.
Leet speak (written as: L33T or 1337) is the most common language on MMORPGs because rude words are not stopped by filters. This language is changing all the time because new words are made and used. A lot of the words use numbers instead of letters but some were made because of typing errors which are now done on purpose. Also, some suffixes are used, such as "-age" and "-ness".
Some of the numbers and symbols used instead of letters are in the table below. |
Nauru | Nauru, ( ) officially the Republic of Nauru, is a sovereign island nation located in the Micronesian South Pacific. Its nearest neighbour is Banaba Island in the Republic of Kiribati, due east. Nauru is the world's smallest island nation, covering just , the smallest independent republic, and the only republican state in the world without an official capital. With 10,670 residents, it is the third least-populated country after Vatican City and Tuvalu.
Nauru is a phosphate rock island, and its primary economic activity since 1907 has been the export of phosphate mined from the island. English and Nauruan are the official languages of Nauru. The current president of Nauru is Lionel Aingimea.
Nauru is a oval-shaped island in the southwestern Pacific Ocean, south of the Equator. The island is surrounded by a coral reef, which is exposed at low tide and dotted with pinnacles. The presence of the reef has prevented the establishment of a seaport, although channels in the reef allow small boats access to the island. A fertile coastal strip wide lies inland from the beach.
Coral cliffs surround Nauru's central plateau. The highest point of the plateau, called the Command Ridge, is above sea level. The only fertile areas on Nauru are on the narrow coastal belt, where coconut palms flourish. The land surrounding Buada Lagoon supports bananas, pineapples, vegetables, pandanus trees, and indigenous hardwoods such as the tomano tree.
Nauru was one of three great phosphate rock islands in the Pacific Ocean (the others were Banaba (Ocean Island) in Kiribati and Makatea in French Polynesia). The phosphate reserves on Nauru are now almost entirely depleted. Phosphate mining in the central plateau has left a barren terrain of jagged limestone pinnacles up to high. Mining has stripped and devastated about 80 per cent of Nauru's land area, and has also affected the surrounding Exclusive Economic Zone; 40 per cent of marine life is estimated to have been killed by silt and phosphate runoff.
There are only about 60 recorded vascular plant species native to the island, none of which are endemic. Coconut farming, mining, and introduced species have caused serious disturbance to the native vegetation. There are no native land mammals, but there are native insects, land crabs, and birds, including the endemic Nauru Reed Warbler. The Polynesian rat, cats, dogs, pigs, and chickens have been introduced to Nauru from ships.
There are limited natural fresh water resources on Nauru. Rooftop storage tanks collect rainwater, but the islanders are mostly dependent on three desalination plants housed at Nauru's Utilities Agency. Nauru's climate is hot and very humid year-round because of its proximity to the equator and the ocean. Nauru is hit by monsoon rains between November and February, but does not typically experience cyclones. Annual rainfall is highly variable and is influenced by the El Niño-Southern Oscillation, with several significant recorded droughts. The temperature on Nauru ranges between and during the day and between and at night.
As an island, Nauru is vulnerable to climate and sea level change. Nauru is the seventh most global warming threatened nation due to flooding. At least 80 per cent of the land of Nauru is well elevated, but this area will be uninhabitable until the phosphate mining rehabilitation programme is implemented.
Nauru is divided into fourteen administrative districts which are grouped into eight electoral constituencies. |
Noun | A noun is a kind of word (see part of speech) that is usually the name of something such as a person, place, thing, animal, or idea. In English, nouns can be singular or plural.
Nouns often need a word called an article or (like "the" or "that"). These words usually do not go with other kinds of words like verbs or adverbs. (For example, people do not also describe nouns). In English, there are more nouns than any other kind of word.
Every language in the world has nouns, but they are not always used in the same ways. They also can have different properties in different languages. In some other languages, nouns do not change for singular and plural, and sometimes there is no word for "the".
Examples of nouns: "time, people, way, year, government, day, world, life, work, part, number, house, system, company, end, party, information".
The word noun comes from the Latin "nomen" meaning "name." Words like nouns were described in early days by the Sanskrit grammarian and ancient Greeks like Dionysios Thrax.
In English sentences, nouns can be used as a subject, object, or complement. They often come after prepositions, as the 'object of preposition'.
Nouns can sometimes describe other nouns (such as a soccer ball). When they do this, they are called modifiers or adjuncts.
There are also verb forms that can be used in the same way as nouns (such as 'I like "running".') These are called "verbals" or "verbal nouns", and include "participles" (which can also be adjectives) and "infinitives".
Nouns are classified into common and proper. Pronouns have commonly been considered a different part of speech from nouns, but in the past some grammars have included them as nouns as do many modern linguists.
Proper nouns (also called proper name) are specific names. Examples of proper nouns are: "London, John, God, October, Mozart, Saturday, Coke, Mr. Brown, Atlantic Ocean." Proper nouns are individual things with names, not general nouns.
Proper nouns begin with an (capital) letter in English and many other languages that use the Roman alphabet. (However, in German, all nouns begin with an upper case letter.) The word "I" is really a pronoun, although it is capitalized in English, like a proper noun.
Some common nouns (see below) can also be used as proper nouns. For example, someone might be named 'Tiger Smith' -- even though he is not a tiger or a smith.
Common nouns are general names. Sometimes the same word can be either a common noun or a proper noun, depending on how it is used; for example:
In English and many other languages, nouns have 'number'. But some nouns are only singular (such as "furniture, physics") and others are only plural (such as "clothes, police"). Also, some nouns are countable (for example, "one piece, two pieces") but others are uncountable (for example, we do not say "one furniture, two furnitures").
The plural form of most nouns is created simply by adding the letter(s) -(e)s.
Despite plural forms being written using the letter(s) -(e)s, the pronunciation of the letter(s) will pronounced as /-s/, /-z/, or /-ız/ depending on which type of phoneme, or unique sound, comes before it. These variations of the plural morpheme are called allomorphs.
Some dictionaries list "busses" as an acceptable plural for "bus". Presumably, this is because the plural "buses" looks like it ought to rhyme with the plural of "fuse," which is "fuses." "Buses" is still listed as the preferable plural form. "Busses" is the plural for "buss," a seldom used word for "kiss."
There are several nouns that have irregular plural forms. Plurals formed in this way are sometimes called mutated (or mutating) plurals.
Many of the above irregular plural forms stem from Old English, which had more complex rules for making plural forms.
And, finally, there are nouns that maintain their Latin or Greek form in the plural.
Nouns are words for things, and since things can be possessed, nouns can also change to show possession in grammar. In English, we usually add an apostrophe and an "s" to nouns to make them "possessive", or sometimes just an apostrophe when there is already an "s" at the end, like this:
Most adjectives become nouns by adding the suffix -ness. Example: Take the adjective 'natural', add 'ness' to get 'naturalness', a noun. To see a list of 100 adjectives used in Basic English, click here.
A noun phrase is a phrase where the head word is a noun. In English, the word order of most noun phrases is that determiners, adjectives, and modifying nouns in respective order must appear before the head word, and relative clauses must appear after the head word. |
Nature | The words nature and natural are used for all the things that are normally not made by humans. Things like weather, organisms, landforms, celestial bodies and much more are part of nature. Scientists study the way the parts of nature work. Things that have been made by people are said to be man-made or called artifacts.
There are natural sciences that study different parts of nature, for example the science of ecology is about plants and animals as a whole, while biology studies every type of living thing.
From one point of view, humans are a prime example of nature, and are the most widely studied natural inhabitants of the planet earth. Humans interact with each other in their natural environment on a day-to-day basis. Every part of nature everything from the air outside to the dirt on the ground is interdependent. Medicine studies humans in health and sickness.
From another point of view, humans and nature can be said to be in conflict. Nature is often seen by humans as natural resources. People cut down trees, mine ores, and grow crops. Fires, cars, and factories make a lot of smoke and harm many places. People who like to leave nature unharmed and those who feel they need to use more of nature often fight about what they should do. In the modern world, with many more people and many big cities, these problems are becoming more serious.
Nature, in the broadest sense, means the physical world as a whole. This is the meaning that physics, the study of nature (etymologically), takes.
A useful definition of "natural" is |
Natural resource | A natural resource is what people can use which comes from the natural environment. Examples of natural resources are air, water, wood, oil, wind energy, natural gas, iron, and coal.
The dividing line between natural resources and man-made resources is not clear-cut. Hydro-electric energy is not a natural resource because people use turbines to convert the energy from moving water. Petroleum and iron ores are natural, but need work to make them into usable refined oil and steel. Atomic energy comes from metallic nuclear fuels, like fissionable uranium and plutonium, but natural rocks need technical work to make them into these nuclear fuels.
We often say there are two sorts of natural resources: renewable resources and non-renewable resources.
Most natural resources are limited. This means they will eventually run out. A perpetual resource has a never-ending supply. Some examples of perpetual resources include solar energy, tidal energy, and wind energy. There may be a limit to how much can be taken in a given day or year, but that amount can be taken again next day or next year.
Non perpetual resources include Fossil fuels such as Petroleum,coal ,etc. They have a limit of usage.
Some of the things influencing supply of resources include whether it is able to be recycled, and the availability of suitable substitutes for the material. Non-renewable resources cannot be recycled. For example, fossil fuels cannot be recycled.
The demand for resources can change with new technology, new needs, and new economics (e.g. changes in cost of the resources). Some material can go completely out of use, if people do not want it any more. Demand of many natural resources is very high, but availability of some, such as precious metals, is very low.
Different places have different natural resources. When people do not have a certain resource they need, they can either replace it with another resource, or trade with another country to get the resource. People have sometimes fought to have them (for example, spices, water, arable farmland, gold, or petroleum).
When people do not have some resources, their quality of life can get lower. So, people protect resources. When they can not get clean water, people may become ill; if there is not enough wood, trees will be cut and the forest will disappear over time (deforestation); if there are not enough fish in a sea, people can die of starvation. Renewable resources include crops, wind, hydroelectric power, fish, and sunlight. Many people carefully save their natural resources so that others can use them in future. |
Negentropy | Negentropy is reverse entropy. It means things becoming more in order. By 'order' is meant organisation, structure and function: the opposite of randomness or chaos. One example of negentropy is a star system such as the Solar System. Another example is life.
As a general rule, everything in the universe tends towards entropy. Star systems eventually become dead. All energy has gone, and everything in the system is "at the temperature of the surrounding space". The opposite of entropy is negentropy. It is a temporary condition in which certain things are hotter and more highly organised than the surrounding space. This is the second law of thermodynamics:
Life is considered to be negentropic because it converts things which have less order, such as food, into things with more order, such as cells in the body, tissues, and organs. In doing so, it gives off heat. Another example of negentropic things are societies, or social systems, because they take disorderly things such as communications, and make them more orderly and useful. |
North America | North America is a large continent in the Northern and Western Hemispheres of Earth. It is to the east of the Pacific Ocean, the west of the Atlantic Ocean, the south of the Arctic Ocean, and it is the northern part of the Americas. The southernmost part is Central America. It is the third largest continent in the world, after Asia and Africa. North America has a population of around 371 million and is the 4th most populous continent in the world.
Hundreds of millions of years ago, North America was part of a larger ancient supercontinent named Laurasia. A few million years ago, a new land bridge arose and connected North America to South America. Beringia connected North America to Siberia a few times during ice ages in the past 20,000 years. North America has lots of hot and nice tropical islands such as the Bahamas. North America is currently north of South America. |
Neptune | Neptune is the eighth and last planet from the Sun in the Solar System. It is an ice giant. It is the fourth largest planet and third heaviest. Neptune has five rings which are hard to see from the Earth. It is seventeen times heavier than Earth and is a little bit heavier than Uranus. It was named after the Roman God of the Sea.
Neptune's atmosphere is mostly made up of hydrogen and helium. It also contains small amounts of methane which makes the planet appear blue. Neptune's blue color is much darker compared to the color of Uranus. This planet also has the strongest winds of any planet in the Solar System, measured as high as 2,100 km/h or 1,300 mph.
Neptune was discovered by the astronomers Urbain Le Verrier and John Couch Adams. They were both honored for the discovery. The planet was the first to be discovered by mathematical calculations instead of using a telescope. In 1821, it was found that Uranus' orbit had some differences from its expected orbit. So astronomers searched for another new planet.
The planet was visited by only one spacecraft, "Voyager 2" on 25 August 1989. Neptune once had a huge storm known as the "Great Dark Spot" which was discovered in 1989 by Voyager 2. However, the dark spot was not seen in 1994, and new spots were found since then. It is not known why the dark spot disappeared. Visits by more space probes have been proposed.
The first possible sighting of Neptune is thought to be by Galileo as his drawings showed Neptune near Jupiter. But Galileo was not credited for the discovery since he thought Neptune was a "fixed star" instead of a planet. Because of Neptune's slow movement across the sky, Galileo's small telescope was not strong enough to detect Neptune as a planet.
In 1821, Alexis Bouvard published the astronomical tables of the orbit of Uranus. Later observations showed that Uranus was moving in an irregular way in its orbit. Therefore some astronomers thought of another large body. In 1843, John Couch Adams calculated the orbit of an eighth planet that would possibly be influencing the orbit of Uranus. He sent his calculations to Sir George Airy, the Astronomer Royal, who asked Adams for an explanation. In 1846, Urbain Le Verrier, who was not working with Adams, made his own calculations but also failed to get much attention from French astronomers. However, in the same year, John Herschel began to support the mathematical method and encouraged James Challis to search for the planet. After much delay, Challis began his unwilling search in July 1846. Meanwhile, Le Verrier had convinced Johann Gottfried Galle to search for the planet.
Heinrich d'Arrest, a student at the Berlin Observatory, suggested the following. A newly drawn map of the sky in the region of Le Verrier's predicted area could be compared with the current sky. It was needed to look for the change of position of a planet, compared to a fixed star. Neptune was then discovered that very night on 23 September 1846, within 1° (one degree (angle)) of where Le Verrier had predicted it to be, and about 10° from Adams' prediction. Challis later found out that he had seen the planet twice in August, failing to recognize it due to his careless work approach.
When Neptune was discovered, there was also a lot of arguing between the French and the British. It was about who was to deserve credit for the discovery. Later, an international agreement decided that both Le Verrier and Adams together deserved credit. However, historians reviewed the topic after the rediscovery in 1998 of the "Neptune papers" (historical documents from the Royal Greenwich Observatory). It had seemingly been stolen and kept by astronomer Olin Eggen for nearly three decades and was only rediscovered (in his ownership) shortly after his death. After reviewing the documents, some historians now think that Adams does not deserve equal credit with Le Verrier.
Shortly after its discovery, Neptune was temporarily called "the planet exterior to Uranus" or "Le Verrier's planet". The first suggestion for a name came from Galle. He proposed the name "Janus". In England, Challis suggested the name "Oceanus". In France, Arago suggested that the new planet be called "Leverrier", a suggestion which was met with a lot of opposition outside France. French almanacs quickly reintroduced the name "Herschel" for "Uranus" and "Leverrier" for the new planet.
Meanwhile, Adams suggested changing the name "Georgian" to "Uranus", while Leverrier (through the Board of Longitude) suggested "Neptune" for the new planet. Struve gave support of that name on 29 December 1846, to the Saint Petersburg Academy of Sciences. Soon "Neptune" was internationally agreed among many people. It was the official name for the new planet. In Roman mythology, Neptune was the god of the sea, identified with the Greek god, Poseidon.
At 102.413kg, Neptune's mass puts the planet between Earth and the largest gas giants. Neptune has seventeen Earth masses but just 1/18th the mass of Jupiter. Neptune and Uranus are often considered to be part of a sub-class of a gas giant known as ""ice giants"." It is given their smaller size and big differences in composition compared to Jupiter and Saturn. In the search for extrasolar planets, Neptune has been used as a reference to determine the size and structure of the discovered planet. Some discovered planets that have similar masses like Neptune are often called "Neptunes."
The atmosphere of Neptune is made up mostly of hydrogen, with a smaller amount of helium. A tiny amount of methane was also detected in the atmosphere. The methane gives Neptune its blue color.
Because of Neptune's far distance from the Sun, it gets very little heat. The average temperature on Neptune is about -201°C (−331 °F; 72 K). Therefore, Neptune is the coldest planet in the Solar System. But in the depths of planet the temperature rises slowly. The source of this heating is unknown. Neptune is the farthest planet from the Sun, yet its internal energy is strong enough to create the fastest winds seen in the Solar System. Several possible explanations have been suggested. Firstly, radiogenic heating from the planet's core. Among the explanations is the continued radiation into space of leftover heat made by infalling matter during the planet's birth. The last explanation is gravity waves breaking above the tropopause.
The structure of the inside of Neptune is thought to be very similar to the structure of the inside of Uranus. There is likely to be a core, thought to be about 15 Earth masses. It is made up of molten rock and metal surrounded by rock, water, ammonia, and methane. This mixture is referred to as icy. It is called a water-ammonia ocean. More mixtures of methane, ammonia, and water are found in the lower areas of the atmosphere.
At a depth of 7, 000 km of Neptune, the conditions may be such that methane decomposes into the diamond crystals. These diamond crystals resemble hailstones.
The pressure at the center of Neptune is millions of times more than that on the surface of Earth.
One difference between Neptune and Uranus is the level of meteorological activity that has been observed. When the Voyager spacecraft flew by Uranus in 1986, the winds on that planet were observed to be mild. When Voyager flew by Neptune in 1989, powerful weather events were observed. The weather of Neptune has extremely active storm systems. It's atmosphere has the highest wind speeds in the Solar System, thought to be powered by internal heat flow. Regular winds in the equatorial region have speeds of around 1,200 km/h (750 mph). Winds in storm systems can reach up to 2,100 km/h, near-supersonic speeds.
In 1989, the Great Dark Spot, an anticyclonic storm system, was discovered by NASA's "Voyager 2" spacecraft. The storm resembled the Great Red Spot of Jupiter. However, on 2 November 1994, the Hubble Space Telescope did not see the Great Dark Spot on the planet. Instead, a new storm similar to the Great Dark Spot was found in the planet's northern hemisphere. The reason why the Great Dark Spot has disappeared is unknown. The Scooter is another storm, a white cloud group farther south than the Great Dark Spot. Its nickname was given when first noticed in the months leading up to the "Voyager" encounter in 1989. It moved faster than the Great Dark Spot. Later images showed clouds that moved even faster than Scooter. The Wizard's Eye/"Dark Spot 2" is another southern cyclonic storm, the second strongest storm seen during the 1989 encounter. It originally was completely dark, but as "Voyager" came closer to the planet, a bright core developed.
Neptune also has similarities with Uranus in its magnetosphere. The magnetic field strongly tilted comparative to its rotational axis at 47° and offset at least 0.55 radii (about 13,500 kilometres) from the planet's physical center. The scientists think the extreme course may be characteristic of flows in the interior of the planet.
Tiny blue-colored rings have been discovered around the blue planet. They are not as well known as the rings of Saturn. When these rings were discovered by a team led by Edward Guinan, originally, they thought that the rings might not be complete. However, this was proven wrong by "Voyager 2". Neptune's planetary rings have a weird "clumpy" arrangement. The scientists think that it may be because of the gravitational contact with small moons that orbit near them.
Proof that the rings are incomplete first began in the mid-1980s, when stellar occultation were found to rarely show an extra "blink" just before or after the planet occulted the star. Pictures from "Voyager 2" in 1989 solved the problem when the ring system was found to have several faint rings. The farthest ring, Adams, has three famous arcs now named "Liberté", "Egalité", and "Fraternité" (Liberty, Equality, and Fraternity).
The existence of arcs is tough to understand because the laws of motion would predict that arcs spread out into a single ring in a very short time. The gravitational effects of Galatea, a moon just inward from the ring, are now thought to have created the arcs.
New Earth-based observations published in 2005 appeared to show that Neptune's rings are a lot more unstable than thought before. To be exact, it looks like that the "Liberté" ring may disappear in less than 100 years. The new observations seem to puzzle our understanding of Neptune's rings into a lot of confusion.
Neptune has a total of 14 known moons. As Neptune was the Roman god of the sea, the planet's moons were named after lesser sea gods or goddesses.
The largest moon, and the only one big enough to have the shape of a sphere is Triton. Triton was discovered on October 10, 1846 by British astronomer William Lassell. Unlike all other large planetary moons, Triton moves in the other direction than the other moons. This shows the moon was probably captured and maybe was once a Kuiper belt object. It is close enough to Neptune to be locked into a synchronous orbit. It is also slowly moving into Neptune and will one day be torn apart when it passes the Roche limit. Triton is the coldest object that has been measured in the Solar System, with temperatures of −235°C (38 K, −392 °F).
Neptune's second known moon (by order of distance), the odd moon Nereid, has one of the most unusual orbits of any satellite in the Solar System.
From July to September 1989, "Voyager 2" discovered six new moons of Neptune. Of these, Proteus is the second most massive Neptunian moon. It has only one quarter of 1% of the mass of Triton. Neptune's closest four moons, Naiad, Thalassa, Despina, and Galatea, orbit close enough to be inside Neptune's rings. The next farthest out, Larissa was originally discovered in 1981 when it had occulted a star. The moon was credited for causing Neptune's ring arcs when "Voyager 2" observed Neptune in 1989. Five new unusual moons discovered between 2002 and 2003 were announced in 2004. The latest moon, Hippocamp, was discovered from examining Hubble Telescope images on 16 July 2013.
Neptune cannot be seen with naked eye alone, since Neptune's normal brightness are between magnitudes +7.7 and +8.0. It can be out-shined by Jupiter's Galilean moons, the dwarf planet Ceres, and the asteroids 4 Vesta, 2 Pallas, 7 Iris, 3 Juno and 6 Hebe. A telescope or strong binoculars will show Neptune as a small blue dot that looks similar to Uranus. The blue color comes from the methane in its atmosphere. Its small obvious size has made it difficult to study visually. Most telescopic data was quite limited until the arrival of the Hubble Space Telescope and large ground-based telescopes with adaptive optics.
With an orbital period (sidereal period) of 164.88 Julian years, Neptune was returning to the same place in the sky where it was discovered in 1846. In August 2011, it completed its first full orbit of the Sun. It happened three different times, also with a fourth in which it came very close to being at that position. This is explained by the idea of retrogradation.
Currently, only one spacecraft has visited Neptune. NASA's "Voyager 2" probe made a quick flyby of the planet with its closest encounter on 25 August 1989. It was the last planet to have been visited by a spacecraft.
One of "Voyager 2"'s important discoveries was its very close fly-by of Triton where took pictures of several parts of the moon. The probe also discovered the Great Dark Spot. However, it had now disappeared after the Hubble Space Telescope took pictures of Neptune in 1994. Originally thought to be a large cloud or cyclonic storm system. It was later guessed to be a hole in the visible cloud deck.
The pictures sent back to Earth from "Voyager 2" in 1989 became the basis of a PBS all-night program called "Neptune All Night".
After the "Voyager 2" flyby mission comes "Flagship orbital mission". This hypothetical mission is not possible until the late 2020s or early 2030s.
"Neptune Odyssey" is the current mission concept for a Neptune orbiter. NASA's possible large strategic science mission would launch in 2033 and arrive at Neptune in 2049. |
Negative | Negative may mean: |
Now | Now is the time span between the past and the future. It can be long (like an eon in geologic time) or short (like a picosecond) but it is almost always used to refer to the span between the present instant to some time horizon when a decision must be made. It can be used to ask or demand that someone make a decision even if they want to delay.
"I want to know what you think, now."
"What do you think now?"
"Now is the time for all good people to come to the aid of their country."
Mathematics and measurement assume that everything used in one equation equals the same quantities at the beginning of calculation or axiomatization as at the end. That means it is mathematically correct to say that the idea of "equal" means "equal from the time the process starts to the time it ends." In General Semantics and E Prime the words equal, remain (for the past until now) and become (for now into the future) replace the verb "to be" for this reason.
Algebra is now often called snapshot algebra or algebra of seeing because of this dependence on time. If any action or event were possible between steps in algebraic analysis, then, in theory, one would have to start over as if one had no knowledge of the new state at all. For these reasons the idea of statistics and also knowledge and knowledge management are sometimes questioned, for instance, in the book "Lies, Damn Lies, and Statistics". A major issue is the comparing of numbers gathered in the past, and now, after some key conditions change. |
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