1. [From the Usenet group
alt.folklore.urban] To utter a posting on Usenet
designed to attract predictable responses or flames; or, the
post itself. Derives from the phrase "trolling for newbies"
which in turn comes from mainstream "trolling", a style of
fishing in which one trails bait through a likely spot hoping for a
bite. The well-constructed troll is a post that induces lots of
newbies and flamers to make themselves look even more clueless than
they already do, while subtly conveying to the more savvy and
experienced that it is in fact a deliberate troll. If you don't
fall for the joke, you get to be in on it. See also YHBT. 2.
An individual who chronically trolls in sense 1; regularly posts
specious arguments, flames or personal attacks to a newsgroup,
discussion list, or in email for no other purpose than to annoy
someone or disrupt a discussion. Trolls are recognizable by the
fact that the have no real interest in learning about the topic at
hand - they simply want to utter flame bait. Like the ugly
creatures they are named after, they exhibit no redeeming
characteristics, and as such, they are recognized as a lower form
of life on the net, as in, "Oh, ignore him, he's just a troll."
3. [Berkeley] Computer lab monitor. A popular campus job for CS
students. Duties include helping newbies and ensuring that lab
policies are followed. Probably so-called because it involves
lurking in dark cavelike corners.
Some people claim that the troll (sense 1) is properly a narrower category
than flame bait, that a troll is categorized by containing
some assertion that is wrong but not overtly controversial. See
also Troll-O-Meter.