People often make mistakes assuming that someone who trolls is called a troller, when really, there is no such thing.
Someone who trolls is correctly called a troll.

Someone who likes to troll, a person who either intentionally or pointlessly yells and swears and insults someone with no or some purpose. Usually spawned by agruements, disagreements, or just hatred. Trolling can also be conducted as a self-entertainment to the troller by causing a ignition in chat or in a internet forum.

Trolling is usually accompanied with spam, capital letters, bad grammar, and immature comments. They can be racist, elitest, or anything else that has to do with stereotypes.

Someone who uses their pic as if fishing by trailing a line, as from a moving boat but in Internet chat rooms day and night until they nab a catch.

A troller, or troll (pronounced trall) is a person who purposely makes comments on controversial topics designed to piss people off. A troller is always watching his/her comment, so the best thing to do is ignore it. But if you want to make a trollers day, play along. I guarantee they'll be happy. Trollers are everywhere that people are seeing live feeds in forums to YouTube comments. Trolls are hard to upset, in fact, much of what you do to shame them, just makes them laugh louder. There are many kinds of trolls, from eleven year olds to hard core trollers. Depending on the content of the trollers comment, you can tell fairly easily.

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