Definition:
In contrast to viruses, computer worms are malicious programs that copy themselves from system to system, rather than infiltrating legitimate files. For example, a mass-mailing email worm is a worm that sends copies of itself via email. A network worm makes copies of itself throughout a network, an Internet worm sends copies of itself via vulnerable computers on the Internet, and so on.
Also Known As: Email worm, Internet worm, network worm