2. What is a virus?

A computer virus is a software program that is designed to copy itself over and over again and to attach itself to other programs.

In the early days of personal computing (1980's) some of the people who created viruses had a certain misplaced sense of humour. For example, there was a virus that caused all the characters on screen to drop into a heap at the bottom of the display. Very annoying, but relatively harmless.

However, quite soon some really nasty versions came out that were deliberately designed to corrupt and delete your files as well as trying to copy itself everywhere.

Viruses can cause an immense amount of time wasting and financial loss for people and businesses. For example, the "Melissa" virus was so effective in spreading itself that many huge corporations had to shut down their email systems until the virus could be contained.

It is important to understand that viruses do NOT damage the hardware. They affect the data and programs stored on your computer.