For the purposes of this article, we're talking about any software which has malicious intent and which may find its way onto your PC. The simplest way to "catch" virus these days is by email; someone sends you an "infected" file which:

1. Infects your PC in some way.
2. Forwards itself to people in your address book so that they, too, become infected.

There are three key steps to take. First, install a virus checker, and second keep it up to date. An out of date virus checker is almost worse than no virus checker at all, because it gives you a false sense of security.

Virus checkers aimed at small business and home users typically cost £20-£40 and include a year's worth of updates (so you should see the price as an annual charge). There are some good free packages around - we recommend a package called AVG available from www.grisoft.com, which includes free updates, we are also an authorised reseller of AVG should you wish to purchase the Anti-virus software.

The third key step is to keep your PC up to date with updates from Microsoft. You should find "Windows Update" at the top of your Start Menu - use it, often. It's only the "critical updates" that you need, but even so if you don't do this regularly you may find yourself in for a lengthy download. Many PC magazines available from high street newsagents put selections of the updates on their cover CDs, which can save you some time downloading (although the magazine will cost around £4 and that equates to several hours online at weekend rates, so downloading will still probably work out cheaper).

There is some truth in this, but by and large its the people you do know that you have to worry about. Remember that many viruses spread by sending themselves to everyone in your address book. This means that if you get one it's probably come from someone you know, although of-course it won't have been sent deliberately.

No! Or at least check it out first. There are several "hoax" viruses and virus warnings which rely on good natured people forwarding them to spread as far as possible. Some of the more clever ones tell you to look for a specific file on your hard disk for signs of an infection, and of-course they pick a file which is part of Windows so you think you've been infected. You then delete the file and damage your own system... There will usually be a note that most virus checkers don't detect the file - of-course they don't, as its not a virus!

A quick way to check out any virus is to use the Internet search engines. One of the common hoaxes tells you to look for a file called "sulfnbk.exe" and delete it if you find it. Searching for "sulfnbk" at Google ( www.google.com) quickly gives links to plenty of reliable sources which tell me that this is a hoax. One simple step can save you incorrectly deleting files and forwarding the message to all your colleagues and customers.

Experience is the best teacher, but of-course you don't want to wait until you get caught to learn the lessons.

Some simple guidelines:

1. Don't blindly trust emails. Don't assume that because an email says it contains a really funny joke and its from a friend that it really is what it says it is. But don't get paranoid either; a decent virus checker will spot most problems and a bit of common sense will catch the rest.
2. Be wary of attachments. Viewing an infected email will normally not cause a problem, opening any attachments that come with it is where the problems start. But see the next point:
3. Keep up to date with Microsoft security updates. A recently discovered (and now fixed) bug in Windows and Outlook / Outlook Express allowed virus code to be run when an email is viewed, without intentionally opening the attachment. Unless you install the update, you're vulnerable.
4. Keep backups!!! Obvious, of-course, but how many people can really say that they do this? The thing with backups is that one day you will need them. Whether the PC breaks, gets stolen, or gets infected by a virus, one day you'll need to use your backups - so keep them up to date. For many people the simplest option is to buy a CD writer and copy important files to blank CDs - the writer should cost you well under £75 and blank disks start at 20p each these days. Another option is to sign up to an offsite backup service, more information on such a service can be found here.