An "Internet troll" or "Forum Troll" or "Message Board Troll" is a person who posts outrageous message to bait people to answer. Forum Troll delights in sowing discord on the forums. A troll is someone who inspires flaming rhetoric, someone who is purposely provoking and pulling people into flaming discussion. Flaming discussions usually end with name calling and a flame war.

A classic troll is trying to make us believe that he is a genuine skeptic with no hidden agenda. He is divisive and argumentative with need-to-be-right attitude, "searching for the truth", flaming discussion, and sometimes insulting people or provoking people to insult him. Troll is usually an expert in reusing the same words of its opponents and in turning it against them.
While sometimes, he may sound like a stupid, uninformed, ignorant poster, do not be deceived! Most trolls are highly intelligent people trying to hide behind a mask of stupidity and/or ignorance! They usually have an agenda.

He is generally interested to make other forum members look stupid. A troll will sometimes use insults to provoke other people to insult him. Then, he will complain to moderators of being insulted and will request that his opponents get banned from further discussion.
I thought people might like to know what a troll is.

People will be banned if they constantly answer to this description.