Computer security- different types of hats (hackers)

in this essay, u must only focus on different groups of hackers which are black hats, white hats, red hats, grey hats

provide information of each group, for example is there any organization of each group. 

you must be able to give real examples on each group. and also must state that what are their motivations of hacking.

State your opinions on each group with supporting evidence

3 and half pages with references