Could someone please explain what a "troll" is, and how can you identify one?

Definition of 'Troll' according to Yahoo (so it MUST be true):

A "troll" is someone who intentionally and persistently posts inflammatory messages about sensitive topics to bait users into responding or provoke a confrontation. We also consider people to be trolls when they persistently misuse product features such as the ratings system to negatively target others.

It is something which is not natural and I understand they can be very small or a giant. Maradona reminded me of a troll.

People who ask stupid or insulting questions just to get a reaction. The term "Troll" comes from the fishing term "trolling" where you are dragging a fishing line behind a moving boat hoping to get some fish to chase the bait and bite.

People who post offensive messages.

a person who hangs around day after day giving meaningless answers.

Mrs GC says it, but this chap has something to say:

http://www.flayme.com/troll/

Oooh

ME seems to have red stop sign, so theres one for a start

The trolls lurk on the net, like trolls in books lurking under bridges. They dont say much, too busy thumbing the report button.......or maybe they do say much and make out they are your friend. I know who i trust here, everyone else can get to fcuk

Edit: LOL @ Rod....bless him :)

Try here... http://en.wikipedia.org/wiki/Internet_troll

and then here...

http://www.teamtechnology.co.uk/troll-tactics.html