We know that Black Holes have two foundamental points of their lives: the birth and the death, as all the stuffs in the universe. About death I remeber that Black Holes evaporates, because of the "Hawking radiations", all the informations that Black Holes swallow during their lives will be thrown out. This theory is difficult to explain and the issue about I want to talk now isn't that, so... the details about their death, if you want, can also be left. About their birth, I don't know anything more than the classical collapse of massive objects and I want to go deeper in this field... I nearly forgot, with the word "Black Holes" I mean all the Black Holes, and not specifical Black Holes... Maybe this could be usefull to rember.