TROJAN HORSE

A destructive program that masquerades as a benign application. Unlike viruses, Trojan horses do not replicate themselves but they can be just as destructive. One of the most insidious types of Trojan horse is a program that claims to rid your computer of viruses but instead introduces viruses onto your computer. The term come from a story in Homer's Iliad, in which the Trojans accepted a gift of a giant wooden horse from their Greek enemies and brought it into the walled city of Troy. Once inside, Greek soldiers hidden in the horse slipped out and opened the gates of the city, allowing the awaiting Greek army to swarm in and quickly capture the city of Troy.