Types of Jinn
Question

I have read in the Holy Quran what a jinn is, but I really don't understand what they really are. Can you please send me more information on them? Peace be unto you!
Praise be to Allah.What are jinn?
The Quran and Sunnah indicate that the jinn exist, and that there is a purpose for their existence in this life, which is to worship Allah Alone, with no partner or associate. Allah says (interpretation of the meanings):
And I (Allah) created not the jinn and humans, except that they should worship Me (Alone). [al-Dhariyat 51:56].
O assembly of jinn and mankind! Did there not come to you messengers from amongst you, reciting unto you My Verses? [al-An'am 6:130]
The world of the jinn is an independent and separate world, with its own distinct nature and features that are hidden from the world of humans. The jinn and humans have some things in common, such as the possession of understanding and the choice between the way of good and the way of evil. The word jinn comes from an Arabic root meaning hidden from sight. Allah says (interpretation of the meaning):
Verily he [Shaytan] and qabiluhu [his soldiers from the jinn or his tribe] see you from where you cannot see them [al-A'raf 7:27]
Origin of jinn
Allah has told us in His Book the essence from which the jinn were created. He says (interpretation of the meaning):
And the jinn, We created aforetime from the smokeless flame of fire. [al-Hijr 15:27]
And the jinns did He create from a smokeless flame of fire. [al-Rahmaan 55:15].
According to a hadith narrated by ‘Aishah, the Prophet (peace and blessings of Allah be upon him) said: The angels were created from light, the jinn were created from fire, and Adam was created from that which has been described to you. (Reported by Muslim, 5314)
Types of jinn in Islam
Allah has created different types of jinn. Among them are some who can take on different forms, such as dogs and snakes; some who are like flying winds with wings; and some who can travel and rest. Abu Tha'labah al-Khushani said: The Messenger of Allah (peace and blessings of Allah be upon him) said: The jinn are of three types: a type that has wings, and they fly through the air; a type that looks like snakes and dogs; and a type that stops for a rest then resumes its journey. (Reported by al-Tahawi in Mushkil al-Athar, 4/95, and by al-Tabarani in al-Kabir, 22/214. Shaykh al-Albani said in al-Mishkat (2/1206, no. 4148): al-Tahawi and Abul-Shaykh reported it with a sahih isnad)
The jinn and the sons of Adam
Every individual among the sons of Adam has a jinn who has been appointed to be his constant companion (qarin). Ibn Mas’ud said: The Messenger of Allah (peace and blessings of Allah be upon him) said, There is not one of you who does not have a jinni appointed to be his constant companion. They said, And you too, O Messenger of Allah? He said, Me too, but Allah has helped me and he has submitted, so that he only helps me to do good. (Reported by Muslim, 2814)
Al-Nawawi said in his commentary on Muslim (17/175): 
“He has submitted: he became a believing Muslim. This is the apparent meaning. Al-Qadi said: Know that the ummah is agreed upon the fact that the Prophet (peace and blessings of Allah be upon him) was protected from Shaytan, physically and mentally, and with regard to his speech. This hadith contains a reference to the warning against the fitnah (temptation, trial) and whispers of the qarin (constant companion from among the jinn). We know that he is with us so we should beware of him as much as possible.”
The powers of the jinn
Allah has given the jinn powers that he has not given to humans. Allah has told us about some of their powers, such as the ability to move and travel quickly. An ‘ifreet from among the jinn guaranteed to the Prophet Sulayman (peace be upon him) that he would bring the throne of the Queen of Yemen to Jerusalem in a moment faster than that needed for a man to get up from where he was sitting. Allah says (interpretation of the meaning):
An ‘ifreet (strong one) from the jinn said: I will bring it [her throne] to you before you rise from your place (council). And verily, I am indeed strong, and trustworthy for such work. One with whom was knowledge of the Scripture said: I will bring it to you within the twinkling of an eye! Then when Sulayman saw it placed before him, he said, This is by the Grace of my Lord [al-Naml 27:39-40].
Food and drink of the jinn
The jinn eat and drink. Ibn Mas’ud said: The Messenger of Allah (peace and blessings of Allah be upon him) said: Someone from among the jinn called me, and I went with him and recited the Quran for them. He took us and showed us the traces of where they had been and the traces of their fires. They asked him for food and he said, You can have every bone on which the name of Allah has been mentioned that comes into your possession, as meat, and all the droppings as food for your animals. The Prophet (peace and blessings of Allah be upon him) said, So do not use [these things] for cleaning yourselves [after relieving oneself], for they are the food and provision of your brothers. (Reported by Muslim, 450). 
According to another report: A delegation of jinn from Nasibin came to me, and what good jinn they are! They asked me for food and I prayed to Allah for them, so that they would not pass by bones or droppings, but they would find food on them. (Reported by al-Bukhari, 3571). The believing jinn may eat any bone on which the name of Allah has been mentioned, because the Messenger (peace and blessings of Allah be upon him) did not permit them to have anything on which Allah's name has not been mentioned; those are for the kuffar among the jinn.
The beasts of the jinn
According to the hadith narrated by Ibn Mas’ud, that we have quoted above, the jinn asked the Messenger (peace and blessings of Allah be upon him) for provision, and he said to them: and [you can have] all the droppings as food for your animals.
The dwelling-places of the jinn
The jinn live on this earth where we do. They are mostly to be found in ruins and unclean places like bathrooms, dunghills, garbage dumps and graveyards. Hence the Prophet (peace and blessings of Allah be upon him) taught us to take precautions when entering such places, by reciting the adhkar (words of remembrance) prescribed in Islam. One of these was reported by Anas ibn Malik (may Allah be pleased with him), who said: When the Messenger of Allah (peace and blessings of Allah be upon him) entered the toilet, he would say, Allahumma innee a'udhu bika min al-khubuthi wal-khabaith (O Allah, I seek refuge with You from the evil ones, male and female).
(Reported by al-Bukhari, 142; and Muslim, 375). Al-Khattabi explained that khubuth is the plural of khabith (evil or dirty masculine form), and khabaith is the plural of khabithah (evil or dirty feminine form), and that what is meant is male and female shayatin.
Some jinn are Muslims and some are unbelievers
Allah tells us that some of the jinn said (interpretation of the meaning):
And some of us are Muslims, and some of us are al-qasitun (disbelievers those who have deviated from the Right Path). And whosoever has embraced Islam, then such have sought the Right Path. And as for the qasitun, they shall be firewood for Hell. [al-Jinn 72:14-15]
The Muslims among the jinn are of different levels as regards righteousness and taqwa. Allah says (interpretation of the meaning):
[Some jinn said:] There are among us some that are righteous, and some the contrary; we are groups, each having a different way (religious sects, etc.) [al-Jinn 72:11]
The story of how the first jinn of this ummah became Muslim was narrated by Abd-Allah ibn Abbas, who said: The Prophet (peace and blessings of Allaah be upon him) went out with a group of his Companions heading for the marketplace of Ukaz. This was when the shayatهn were prevented from getting any news from heaven, and shooting stars had been sent against them. The shayatهn went back to their people, who said, What is the matter with you? They said, We cannot get news from heaven, and shooting stars were sent against us. Their people said, Nothing is stopping you from hearing news from heaven except some new event that must have happened. Go and look in the east and the west of the earth, and see if you can find out what it is that is stopping you from hearing news from heaven. Those who went out in the direction of Tihamah came upon the Prophet (peace and blessings of Allah be upon him) in Nakhlah, when he was on his way to Ukaz, and found him leading his Companions in Fajr prayer. When they heard the Quran, they listened to it and said, By Allah, this is what is stopping us from hearing news from heaven. When they went back to their people, they said, O our people, we have heard a wonderful Recital (the Quran). It guides to the Right Path, and we have believed therein, and we shall never join (in worship) anything with our Lord (Allah). [al-Jinn 72:2 interpretation of the meaning]. Then Allah revealed to His Prophet (peace and blessings of Allah be upon him) the words (interpretation of the meaning): Say (O Muhammad): It has been revealed to me that a group of the jinn listened (to this Quran) [al-Jinn 72:1], and Allah revealed to him what the jinn had said. (reported by al-Bukhari, 731).
Their reckoning on the Day of Resurrection
The jinn will be called to account on the day of Resurrection . Mujahid (may Allah have mercy on him) said, concerning the ayah (interpretation of the meaning): but the jinn know well that they have indeed to appear (before Him) (i.e., they will be brought to account) [al-Saffat 37:158]: They will be brought to judgement. Sahih al-Bukhari, Bab Dhikr al-Jinn wa Thawabihim wa Iqabihim.
Protection from the harm of the jinn
Because the jinn can see us while we cannot see them , the Prophet (peace and blessings of Allah be upon him) taught us many ways to protect ourselves from their harm , such as seeking refuge with Allah from the accursed Shaytan, reciting Surat al-Falaq and Surat al-Nas (the last two Surahs of the Quran), and reciting the words taught by Allah in the Quran (interpretation of the meaning): Say: My Lord! I seek refuge with You from the whisperings (suggestions) of the shayatin (devils). And I seek refuge with You, my Lord, lest they may attend (or come near) me. [al-Muminun 23:97-98]
Saying Bismillah (in the Name of Allah) before entering ones home, before eating or drinking, and before having intercourse will also keep the Shaytan from entering the house or partaking with a person in his food, drink and sexual activity. Similarly, mentioning the name of Allah before entering the toilet or taking off one's clothes will prevent the jinn from seeing a person's ‘awrah or harming him, as the Prophet (peace and blessings of Allah be upon him) said, To put a barrier that will prevent the jinn from seeing the ‘awrah of the sons of Adam, let anyone of you say Bismillah when entering the toilet. (Reported by al-Tirmidhi, 551; Sahih al-Jam’i, 3611).
Strength of faith and religion in general will also prevent the jinn from harming a person, so much so that if they were to fight, the one who has faith would win. Abd-Allah ibn Mas’ud (may Allah be pleased with him) said: A man from among the Companions of Muhammad met a man from among the jinn. They wrestled, and the human knocked down the jinni. The human said to him, You look small and skinny to me, and your forearms look like the front paws of a dog. Do all the jinn look like this, or only you? He said, No, by Allah, among them I am strong, but let us wrestle again, and if you defeat me I will teach you something that will do you good. The human said, Fine. He said, Recite, Allah! None has the right to be worshipped but He, the Ever-living, the One Who sustains and protects all that exists [Ayat al-Kursi al-Baqarah 2:255 interpretation of the meaning]. The human said, Fine. He said, You will never recite this in your house but the Shaytan will come out of it like a donkey breaking wind, and he will never come back in until the next morning. (Reported by al-Darimi, 3247)
This is a brief summary about the jinn, and their nature and characteristics. Allah is the Best of protectors and the Most Merciful of those who show mercy.
And Allah knows best.