Viruses:

Viruses – A virus is a small piece of software that replicates itself. A virus might attach itself to a program such as a spreadsheet program. Each time the spreadsheet program runs, the virus runs, too, and it has the chance to reproduce (by attaching to other programs) or wreak havoc. E-mail viruses – An e-mail virus moves around in e-mail messages, and usually replicates itself by automatically mailing itself to dozens of people in the victim’s e-mail address book. Worms – A worm is a small piece of software that uses computer… Read the rest