What are the broad categories of the different types of meditation? I have heard that there is insight meditation (mostly as part of practicing Buddhism) and Samantha (which involves Buddhism, but really just as a tool in the beginning of a meditation).

This question springs from a question below and reading this answer about (Samantha) Anapanasati:
https://buddhism.stackexchange.com/a/9185/8475

Ultimately, I believe that the answers about meditation for this question are inadequate. I may be alone here, but the current answers do not specify a practical technique for meditation (assuming that mindfulness is a subcomponent). Categorizing the different types of meditation may help in for these underlying reasons:


Best type of meditation for attention
Technique for Concentrative Meditation
What exactly differentiates Vipassana from Samatha meditation?


Lastly, I intent to make a venn diagram showing the similarities and such...
Here are related questions:


Does Zen distinguish between concentration and insight meditation?
Buddha's advice regarding meditation practice
THE BROADER CATEGORIES ARE MENTIONED WITHIN SOME OF THE TYPES OF MEDITATIONS LISTED BELOW, and ALSO IS LISTED HERE:

Reflective meditation


There are a series of meditations that can put you in the right frame of mind.  The guardian meditations are one tool to reduce the power of the hindrances.  


Buddhanussati  (reflection on the qualities of the Buddha)
The first guardian meditation is recollection of the Buddha, keeping in mind his Awakening. It is the reflection on the nine supreme qualities of the Buddha.
Metta (Loving Kindness Meditation)
The second guardian meditation is goodwill.  If one is friendly to oneself, that person will not harm himself/herself. If a person is friendly to others, that person would not harm others’ lives. Therefore, the friendship that brings good to oneself and others is called Mettā.
Asubha (Meditation on loathsomeness)
The third guardian meditation - Here one reflects on this very body from the soles of the feet on up, from the crown of the head on down, surrounded by skin and full of various kinds of unclean things: 'In this body there are head hairs, body hairs, nails, teeth, skin, flesh, tendons, bones, bone marrow, kidneys, heart, liver, pleura, spleen, lungs, large intestines, small intestines, gorge, feces, bile, phlegm, pus, blood, sweat, fat, tears, skin-oil, saliva, mucus, fluid in the joints, urine.'
Maranasati (Meditation on the recollection of death)
The fourth guardian meditation - “Mindfulness of death, when developed and cultivated, is of great fruit and benefit, culminating in the deathless, having the deathless as its consummation.” – Anguttara Nikaya 8.7

There are 10 Anussati meditations - 8 reflections and 2 on mindfulness.  Anussati means repeated reflection or constant awareness or mindfulness on some object. 


Dhammanussati (reflection on the qualities of the Dhamma)
. The second of the 10 is Reflecting on the virtues of the Dhamma (Dhammanussati). It is the reflection on the six supreme qualities of the Teaching of the Buddha.
Sanghanussati (reflection on the qualities of the Sangha)
The third of the 10 is the Sangha is the third of the Three Jewels in Buddhism. It is the reflection on the supreme qualities of the ideal community of Noble Ones (ariya-sangha) — those monks, nuns, laywomen, and laymen who, throughout history, have by their own diligent efforts successfully carried out the Buddha's instructions and gained at least a glimpse of the supreme happiness of nibbana. 
Silanussati (meditation about virtue)
The fourth of the 10 is is the recollection of one's own moral virtue.
Devatanussati (meditation about heavenly beings)
This is the fifth of the 10 is this. We should cultivate the Sēkha Bala Dhamma – Saddhā (faith), Sīla (virtue), Sutha (Dhamma knowledge), Thyāga (generosity), and Paññā (wisdom of the Dhamma) – at this present time. These are qualities that are found in the Devas. If you develop them, then there is divinity within you.
Chaganussati (meditation about generosity)
The sixth of the 10 is Chaganussati. - Reflecting on Giving (dana) is one of the integral parts of the practice of Dhamma. When practiced in itself, it is a basis of merit or wholesome kamma, but only when combined with morality, concentration and insight, will it lead to liberation from samsara, the cycle of repeated existence. So it is of the recollection of one's own generosity.
Reflecting on the peace in Nibbana (Upasamanussati)
The 'recollection of the peace of Nibbana', is the last of the 10 recollections anussati. 



3.


Karuna (Compassion meditation)
The way to cultivate Karunā meditation - the second of Four Divine Abodes… May I be free of bodily pains… May I be free of mental pains… May I be physically healthy… May I be mentally healthy… May I live well and happy… I and … (Karunhā meditation can be cultivated in Mahaggata Chētō Vimukkti and Appamānha Chētō Vimukkti methods similar to the Mettā and Mudita meditations.)
Mudita ( Altruistic-joy meditation)
Loving-kindness, compassion, altruistic joy, and equanimity are known as “the Four Divine Abodes (satara brahma viharanha)”.  The third of the group is the cultivation of Muditā to get rid of discontent about wholesome actions… The happiness we feel about others’ progress/wellbeing is Muditā. One can thrive with money, lands, vehicles, and so on by earnest and righteous livelihoods. If we can be happy by seeing such development of others without getting angry about it, it is Muditā. The Buddha preached to cultivate Muditā to get rid of discontent (aratiya) about wholesome actions.
Upekkha (Equanimity meditation)
This is the last of the four. We do this in order to not get upset from the eight vicissitudes of life.  One who practices equanimity will not mourn when sufferings, troubles find that person. He will not get excited when pleasure, happiness find him. He/she will feel all with an indifferent mentality. What we all have to face is the eight vicissitudes of life (ata lō dahama). One shall cultivate equanimity in order to not to worry or sorrow from the eight vicissitudes of life.


4.


Nava Sivatika (Nine cemetery contemplations)
The last exercise in mindfulness of the body is a series of "cemetery meditations," contemplations of the body's disintegration after death, which may be performed either imaginatively, with the aid of pictures, or through direct confrontation with a corpse. By any of these means one obtains a clear mental image of a decomposing body, then applies the process to one's own body, considering: "This body, now so full of life, has the same nature and is subject to the same fate. It cannot escape death, cannot escape disintegration, but must eventually die and decompose."


5.


Cittanupassana (Contemplation of the mind) 
Cittanupassana-satipatthana means mindfulness which is firmly established on thoughts or mental processes, such as thoughts associated with the passions or dissociated from the passions. 


6.


Dhammanupassana (Contemplation of mental objects or thoughts)
Dhammanupassana-satipatthana means mindfulness which is firmly established on phenomena such as nivarana (hindrances), etc. 


Mindfulness


Kayanupassana (Contemplation of the body)
This is the first of the Four Foundations of Mindfulness.  Buddha's advice is to look at the body, as it is, neither getting attached nor developing aversion towards it. The Buddha's advice is to observe and analyze it without being biased by any views or prejudices and to develop mindfulness. Within the first major section on mindfulness of body there are five meditation methods.
(1) mindfulness of breathing (anapanasati)
(2) Satisampajaññya (awareness) meditation in Satara Satipatthana
(3) mindfulness of postures (iriyapatha)
(4) refelection on internal and external impurities and other vital parts (kunapa)
(5) analysis of four elements (dathu)
(6) reflection on nine stages of a dead body (nava seevaththika) 


Concentrative


Mindfulness of Breathing (Anapanasati)
The Buddha explained to Venerable Ananda, “This one factor is Anapanasati, which when developed and pursued brings the Four Foundations of Mindfulness (Cattaro Satipatthana) to completion. The Four Foundations of Mindfulness, when developed and pursued bring the Seven Factors of Enlightenment to completion. The Seven Factors of Enlightenment, when developed and pursued bring Clear Knowing and Release to completion.” in the Ananda Sutta.
Iriya patha (Meditation on postures of the body)**
The postures of the body can be good subjects leading to the proper establishment of concentration. Here one attempts to be mindful of walking, standing, sitting, lying, bending, stretching, eating, drinking, chewing, savouring, defecating and urinating. 


Uncategorized

Dhathu Manasikara (analysis of four elements)
It is the meditation of the four physical elements (dhatu) of nature: Earth, Water, Fire and Wind (pathavi, apo, tejo, and vayo) as Elements of solidity, fluidity, heat and motion.  

Combinations


sati sampajanna


The Pali word for alertness is sampajañña. It doesn’t mean being choicelessly aware of the present, or comprehending the present. Sampajañña means being aware of what you’re doing in the movements of the body, the movements in the mind. This is why mindfulness and alertness should always be paired.