WHAT IS A TROJAN HORSE?

THE TROJAN HORSE:

I have casually referred to a trojan horse file as a virus. In fact, the purists will quite rightly point out that a trojan horse is not a virus. The difference is that a virus is caught by your computer without your knowledge, quite surreptitiously usually whereas a trojan horse is usually accepted gladly by the user, though it is normally perceived to be something it is not.

The Trojan Horse story is one of history's oldest, dating back 2,500 years to when Helen of Sparta was abducted by Paris of Troy. A war between Greece and Troy followed, during which a huge wooden horse was left behind by the Greeks when they supposedly treated. The Trojans were intrigued by the horse and commandeered it after the Greeks' departure. However, the horse was actually a vessel containing enough Greek soldiers to sneak out of its interior at nightfall and open the city gates for the waiting Greek army. And so it was that Troy fell to the Greeks.

Similarly, the trojan horse computer file is one presented to you purporting to be something that it is not, for example a zipped picture archive or a hot new game. You, unsuspectingly, load it onto your hard drive expecting it to work, and it does not. This is usually the first clue to the presence of a trojan horse. It is at this point of time you should be wondering if your virus protection is effective. If you have not updated it in over three months it is quite likely that it is not.

Trojan horse files are not new. They have been around for years. However, they are becoming more complex, more versatile, and the results of their contamination are becoming ever more devastating.

SEE ALSO: Pretty Park, Back Orifice, ExploreZip Worm, MyPics Worm, FunLove 4099, Virus Hoaxes.