We have all heard of computer viruses, but what are they? And what is the best way of getting rid of them?

What They Are

A computer virus is a piece of program code. It, like the biological virus, has the ability to replicate itself. The virus enters your computer without your knowledge and usually has undesirable side effects. These effects usually only take place when certain conditions are met, eg in the year 2000.

What They Do

If your computer gets a virus the sort of effects you might find happening are:

• Blank areas on the screen.
• Falling letters, ie all the letters on the screen drop to the bottom.
• Messages, such as, 'You have run out of memory space'.

These sorts of effects are known as visual effects and do little damage. The following effects are damaging:

• Files are deleted.
• Machine performance is reduced.
• The keyboard locks up.

How You Get Them

Viruses get onto your computer via floppy disks and through the Internet. The best way to protect yourself against a computer virus is to:

• Write-protect your floppy disks.
• Have an anti-virus software installed onto your computer.
• Always make sure you have write-protected back-up copies of everything that is of value on your computer. This includes the operating system.

And How You Get Rid Of Them

To recover from a virus take the following steps and remember, you must have a copy of the operating system disk that is clear of viruses.

• Turn the computer off. This removes any virus code from the computer's memory.
• Restart the computer using the clean operating disk.
• Scan through all disks using an up-to-date virus checker.
• Remove the viruses in the following order: Boot viruses (viruses stored on your floppy disks) and then File viruses (viruses stored on your computer files).

Remember that the best way to protect yourself from a virus is not to borrow floppy disks from people without checking them for viruses first, and that if you do get one it isn't the end of the world, just a nuisance.