Answer:
AIDS is a syndrome that occurs after you are infected with the HIV (human immunodeficiency virus.) It is transmitted by contact to blood or other bodily fluids (semen, breast milk, etc.). It is most commonly transmitted sexually, but many other transmission possibilities exist. There is much controversy as to where and how AIDS started, but it is beleived that it was originally a disease found in chimpanzees and monkeys that mutated to become pathologic to humans as well. No one is truly certain that it was passed from primates to humans via sexually contact or from other possibilities, such as consuming raw primate meat by humans. The strongest evidences suggests that the disease orginated in Africa and was spread by humans traveling between continents.