Introduction:
Computer viruses can be a nightmare. Some can wipe out the information on a hard drive, tie up traffic on a computer network for hours, turn an innocent machine into a zombie and replicate and send themselves to other computers. If you've never had a machine fall victim to a computer virus, you may wonder what the fuss is about. But the concern is understandable
-- according to Consumer Reports, computer viruses helped contribute to $8.5 billion in consumer losses in 2008. Computer viruses are just one kind of online threat, but they're arguably the best known of the bunch.
