Any computer connected to the Internet faces the risk of virus infection. It may be via an email containing an attachment that you open in curiosity; a friend whose computer is infected by a worm that spreads to every address in their email program; or a virus writer that uses a bug in your operating system to plant a virus that deletes your files or launches a Trojan. In some cases your computer may become infected with a virus by visiting a website or merely by connecting to the Internet.
It's important to regularly update your anti-virus software and be aware of all new fraud developments and threats.
Never download software if you're unsure of the source - this includes websites which prompt you to click 'yes' or 'ok' to run a programme or install a browser plug-in.
Be wary of unexpected or suspicious-looking emails from unknown sources. Emails are a common way to spread harmful codes or to trick you into revealing your Internet Banking information.
Anti-virus software protects your computer by watching its entry points e.g. email, web browsing for the arrival of suspicious files (on-access detection) and by checking your hard drive for known viruses at regular intervals (on-demand detection).
It can also monitor floppy disk's, CD/DVD's, memory sticks etc. It works by matching suspicious files on your computer against a database of known malicious code. In this regard it is vital that you keep your anti-virus software up-to-date. Most anti-virus products will clear this malicious software from your computer.
If your computer is infected with a virus, anti-virus software should alert you to the infection. Some alerts are very basic, simply notifying that a virus has been detected and dealt with. Others are more detailed, providing the file names, its location on your computer and the current status of the virus.