I see the word troll used here often. What are people referring to?

I've seen a few people being accused of being a troll, but on back-tracking threads they didn't do anything to be called such. There are those trolls who specialise in accusing people of being a troll for no other reason than their own sick sense of humour; in other words, falsely accuse someone of being a troll.

Anyway. Internet troll, or 'trolling'

[i]... a person who sows discord on the Internet by starting arguments or upsetting people, by posting inflammatory, extraneous, or off-topic messages in an online community (such as a newsgroup, forum, chat room, or blog) with the intent of provoking readers into an emotional ...[/i]

A person who is a fake online or goes against social normality.

Ugly green monsters that live under a bridge.

not these for sure

Norwegian mythology

I don't think I've met any trolls here. Because I haven't been emotionally moved by anything

Generally, people who post with the sole intention of provoking fights, sowing discord on a site.