Malware

Malware is any software that's used for malicious purposes. As if the word malware weren't arcane enough, hackers break it down into further mysterious subcategories such as viruses, worms, Trojan horses, and spyware. There's a lot of overlap among these categories. For example, some viruses are worms; some Trojan horses are really spyware; and some particularly nasty malware programs try and hit every category.

Worms

A worm is a program that propagates itself automatically across a network, from computer to computer. Each computer ends up with a fully functional (and infectious) copy of the worm. Worms are not necessarily malicious. Some worms have been built to clean up after other worms. But many allegedly harmless worms have become ...

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