Computer viruses affect people all over the world. But which ones are the worst of all time The following is a list of some of the most well known viruses and malware to be made public. Most virus protection software (e.g. Norton Antivirus, McAffee, or PC Tools Antivirus) on the market will protect you from these.

Melissa
Combine the illicit thrill of an exotic dancer with the manipulative genius of a hacker and you have one of the worst computer viruses of all time. Melissa was created by David L. Smith, named for his favorite Friday Night Gal, and released into the world on March 26th, 1999. Posing as an email attachment, the self-replicating virus activated when the malicious attachment was opened, then sent itself to the top 50 people in the email client contact list. The damage was so great that some companies had to shut down email programs until the virus was contained. Smith was convicted, fined $5,000 and spent 20 months in jail. Before Melissa, public knowledge of the detriment of malware was previously unknown.

» Read more: Top Computer Viruses