| A virus is a computer program, as small as just a | | | | One thing to remember about any list of "top |
| few lines of code, which loads itself into a host | | | | viruses" is that new ones are coming out all the time. |
| computer without the user's knowledge or | | | | Also, there are certain viruses that have multiple |
| permission. It then performs certain functions, either | | | | variants, close enough to the original to be named |
| benign or damaging, and reproduces itself to spread | | | | something similar (or even identical), further confusing |
| onto other computers, via an e-mail program, | | | | matters for less technologically sophisticated |
| removable media or another "vector." Viruses are | | | | computer users. If that includes you, just make sure |
| distinct from spyware, most worms and the majority | | | | you are reading a recent list or article from a trusted |
| of Trojan horses, although they can fall under the | | | | source of tech info (major media magazines, |
| general heading of "malware," despite the latter term | | | | manufacturer sites, Symantec, government agencies, |
| being of much more recent vintage. | | | | etc.). |