Twitter CEO: 'We suck at dealing with abuse'
An internet troll is someone who posts malign comments online. The intention is to insult or ridicule a group or individual. 
Where does the word come from?
The etymology is complex - there are trails to an old French hunting term troller and a norse one describing a mythological monster.Why did troll catch-on online?
The Internet use of troll probably derives from a slang term used by US naval pilots in the 1970s - see here.So trolls just insult people for fun?
Trolling can simply consist of crude abuse but some self-confessed trolls pride themselves on their cunning attacks on their victims. One strategy is to join a group under false pretences and then goad genuine members of the group with ridiculous, provocative or abusive comments.Are they just an unpleasant nuisance?
Sometimes trolling can have a sinister impact Jojo Moyes revealed in an article in the Daily TelegraphTrolling - posting inflammatory comments on web sites is on the rise. Recent victims include a schoolgirl who committed suicide; a reporter attacked in Egypt; and a pregnant celebrity.
See full article here
Internet Slang Dictionary
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