[from the obvious analogy with biological viruses, via SF] A cracker
program that searches out other programs and `infects' them by
embedding a copy of itself in them, so that they become {Trojan
horse}s. When these programs are executed, the embedded virus is
executed too, thus propagating the `infection'. This normally happens
invisibly to the user. Unlike a {worm}, a virus cannot infect other
computers without assistance. It is propagated by vectors such as
humans trading programs with their friends (see {SEX}). The virus may
do nothing but propagate itself and then allow the program to run
normally. Usually, however, after propagating silently for a while,
it starts doing things like writing cute messages on the terminal or
playing strange tricks with the display (some viruses include nice
{display hack}s). Many nasty viruses, written by particularly
perversely minded {cracker}s, do irreversible damage, like nuking all
the user's files.
In the 1990s, viruses became a serious problem, especially among
Windows users; the lack of security on these machines enables viruses
to spread easily, even infecting the operating system (Unix machines,
by contrast, are immune to such attacks). The production of special
anti-virus software has become an industry, and a number of
exaggerated media reports have caused outbreaks of near hysteria
among users; many {luser}s tend to blame everything that doesn't work
as they had expected on virus attacks. Accordingly, this sense of
virus has passed not only into techspeak but into also popular usage
(where it is often incorrectly used to denote a {worm} or even a
{Trojan horse}). See {phage}; compare {back door}; see also {Unix
conspiracy}.
[glossary]
[Reference(s) to this entry by made by: {live data}{malware}{phage}{replicator}{science-fiction fandom}{SEX}{Trojan horse}{Unix conspiracy}{virgin}{wabbit}{worm}]