Trojan and viruses.

What is a trojan?

A trojan horse could be either:

a) Unauthorized instructions contained within a legitimate program. These

instrcutions perform functions unknown to (and probably unwanted by) the user.

b) A legitimate program that has been altered by the placement of anauthorized

instructions within it. These instructions perform functions unknown to (and

probably unwanted by) the user.

c) Any program that appears to perform a desirable and necessary function but

that (because of unauthorized instructions within it) performs functions

unknown to (and probably unwanted by) the user.

Under a restricted environment (a restricted Unix shell or a restricted

Windows computer), malicious trojans can't do much, since they are restricted

in their actions. But on a home PC, trojans can be lethal and quite

destructive.

Why the name 'trojan horse'?

In the 12th century B.C., Greece declared war on the city of Troy. The dispute

erupted when the prince of Troy abducted the queen of Sparta and declared that

he wanted to make her his wife, which made the Greeks and especially the queen

of Sparta quite furious.

TROY SAVAGE

TROY SAVAGE

TROY SAVAGE

The Greeks gave chase and engaged Troy in a 10-year war, but unfortunately

for them, all of their efforts went down the drain. Troy was simply too well

fortified.

In a last effort, the Greek army pretended to be retreating, leaving behind a

hude wooden horse. The people of Troy saw the horse, and, thinking it was some

kind of a present from the Greeks, pulled the horse into their city, without

knowing that the finest soldiers of Greece were sitting inside it, since the

horse was hollow.

Under the cover of night, the soldiers snuck out and opened the gates of the

city, and later, together with the rest of the army, killed the entire army of

Troy.

This is why...