Many people believe that a worm is actually a virus. A worm is actually considered officially to be a subclass of a virus, but a worm is much more destructive because it does not need any user interaction to replicate and distribute itself. A virus all the other hand, needs action by the user in order to spread.

In fact, some of the largest attacks that you are probably familiar with have actually been a result of a worm and not a virus. These include the worms Sasser and Blaster, which made huge headlines across the world because of the destruction and problems it caused.

Another side effect of a worm is that it can actually "live" on your hard drive and allow someone else to take troll at your computer remotely.

Fortunately, virus protection software can stop a war before it affects your computer, provided you would sure your virus protection is always kept up-to-date at you follow safe surfing habits.