What is a virus, a worm and a Trojan horse?
A virus is a program, which when loaded onto your computer system, will execute itself and cause damage to the system. The virus can spread itself to other computer systems. A worm is a program that is able to replicate itself and disrupts the computer system by making so many copies of itself that it uses up all the system resources. It too can spread itself to other computer systems. A Trojan horse is a malicious program that is disguised as something harmless. Unlike viruses and worms, a Trojan horse cannot replicate itself however it may spread as part of a virus.
