Q: ?
A: A trojan is a program that appears legitimate but contains hidden code (that means instructions) which performs a destructive function. It is NOT a virus since it does not replicate itself (spread to other programs) but does its damage all at once. (source: Cnet.com) An example is that a trojan invasion might delete some files or even your hard drive or address book. Some of more deadly Russian trojans might come with a cute e-mail program (Happpy Days was an example two years ago) or even a music selection but, hidden away it has instructions like "C:prompt delete" or "Deltree C:" So you accept the program or listen to the music and then when you next bootup your hard drive is removed or damaged. Luckily, if you have adequate anti-virus, anti-spyware, a firewall and security software it will include protection against trojans and warn you when you are ABOUT to accept a trojan-laden message. When that happens you merely ask you protector to delete or quarantine the trojan. However, here are a few safeguards you may wish to follow: (1) Get a trojan scan, free. Don't buy the program, just get the scan at www.pctools.com (2) Don't boot from a floppy disk that may contain a trojan or other malware. Boot from your hard drive and then examine the floppy program. If it has malware you will be warned. (3) Avoid downloading anything that has an executable ending like .exe or txt.vbs (4) A trojan example might be : Happy birthday .jpg.vbs or Love-letter-for-you.txt.vb (5) Get a FREE e-mail protector from www.sophos.com/security/notifications (6) Make sure you have a good firewall program. Hope this helps. You've asked a good question.