Computer viruses are getting more prevalent. It is impossible to prevent contact with them unless your computer lives in an isolated glass bubble. Just as human viruses are spread from person to person, computer viruses are spread from computer to computer.

But what is a virus? A virus is a piece of code (software) that attaches itself to a file. Your computer can get infected by having an infected file loaded on to it. So, for example, if you receive files in emails, download things from the web, or have friends who put their pen drives in your USB then you are at risk

Your computer can be infected and you may not know. Some viruses work the minute they infect the computer, others sit there waiting for a certain trigger. This might be the next time you startup your computer or run a program, or it might be waiting for a particular date and time. If you are infected you are also passing the virus on to others. And they pass it on, and on it goes.

The best form of defence is to have an up-to-date virus protection program on your computer. The up-to-date part is important as viruses are created and released every day. Your anti-virus program will download new virus definitions very frequently, even hourly.

There are lots of anti-virus programs out there. Here is a list of those considered to be the best in the field.

BitDefender http://www.bitdefender.com/

CA http://www.ca.com

F-Secure http://www.f-secure.com/

Kaspersky http://www.kaspersky.co.nz http://www.kapersky.com

McAfee http://www.mcafee.com

NOD32 http://www.eset.com

Norton http://shop.symantecstore.com

Panda http://www.pandasecurity.com/

PC Door Guard http://www.astonsoft.com/content/view/21/55/

PC Security Shield http://www.pcsecurityshield.com/

PC Tools http://www.pctools.com/

Protector Plus http://www.pspl.com/

TrendMicro - (Pc-Cillin) http://trendmicro.com