The term Trojan comes from Greek mythology. According to legend, the Greeks presented the citizens of Troy with a large wooden horse in which they had hidden their warriors. The Trojans mistook the horse as a gift or tribute and allowed it to be brought inside the walls of Troy. During the night, Greek soldiers emerged from the wooden horse and took the city of Troy by surprise. Thus, a Trojan is software that does something other than or in addition to its supposed purpose. Specifically, a Trojan is a malicious program that is disguised as a harmless or even helpful software program. For example, a free application that purports to find and kill Spyware might have a Trojan embedded within it. Trojans do not replicate themselves like viruses. They are spread through e-mail attachments and Web downloads. |