Trojan Horses
Trojan Horses:
Trojan Horses are malicious code that claim to do one thing, such as a game, but when run, secretly do other things. For example, Trojan horses can erase your hard drive. However, they cannot replicate themselves. They have to be sent or copied by a user. One famous Trojan horse program was the “BackOrifice”. Computer users did not even realize they had downloaded a Trojan horse program. However, it allowed the designers a “back door” into their computer. This meant they could easily do what they wanted without the user ever knowing it.
One way to prevent getting Trojan horses or other malicious code is to download only from well-known, reputable sites rather than unknown sites.