This is a destructive program that presents itself as a benign application, often designed to protect the user, when in fact it gains unauthorized access to the user’s system. Technically, it is not a virus since the program does not replicate and spread to other computers but can be just as destructive. The term comes from Greek Mythology.

One example of a Trojan Horse is a program available for users to download and will seek and destroy viruses, when in fact it introduces viruses to the system.