Nowadays computers are part of everyday life, and sit along with eating and sleeping as something we all do every day, and although they provide a wealth of information at our fingertips, a way to make jobs which would take hours take minutes, and of course a great source of entertainment, they are not without their frustrating moments, one of these being of course the computer virus.

We've all heard of them, whether it be in the latest company newsletter about the virus attacking your bosses hard drive, or in the news that the latest computer bug will destroy all life as we know it, the computer virus can be an annoying thing, and whether we know it or not, most of us have 'contracted' a virus on our PC at some point, but how much do we know about them? For the large majority of computer users a computer virus is something for the 'Tech Guy' to deal with, and apart from installing anti-virus software there's little we can, or can be bothered, to do.

A computer virus is basically a computer program that has the ability to copy itself and 'infect' a computer without the owner telling it to do so, or even being aware. The term "virus" is also commonly but wrongly used to refer to other types of malicious software such as malware, adware, and spyware programs. A virus in the true sense of the word can only spread from one computer to another when it is taken there, whether that's over a network or the Internet, or carried it on a removable medium such as a floppy disk, CD, DVD, or USB drive. Viruses often increase their chances of spreading to other computers by infecting files on a network file system.

The advent of the internet has meant that viruses can spread much more easily, and regular outbreaks of certain viruses attack computers which are not properly protected by antivirus software . Viruses such as Sasser have in the past knocked out huge networks of computers, putting businesses out of action sometimes for days at a time.