"An internet troll is someone who comes into a discussion and posts comments designed to upset or disrupt the conversation. Often, it seems like there is no real purpose behind their comments except to upset everyone else involved. Trolls will lie, exaggerate, and offend to get a response.
Canadian researchers...conducted two internet studies with over 1,200 people. They gave personality tests to each subject along with a survey about their internet commenting behaviour...looking for evidence that linked trolling with...narcissism, Machiavellianism, psychopathy, and sadistic personality." These traits are more prevalent among internet trolls:
"It might be said that online trolls are prototypical everyday sadists. Both trolls and sadists feel sadistic glee at the distress of others. Sadists just want to have fun...and the Internet is their playground!"
Not surprising, but I think there are two kinds of trolls: those who troll to be funny and those who troll because they want to be malicious and have a problem with people liking what they don't like. The former are jokes, the latter are the psychopaths.
and several news sites? Definitely. Some people are so crazy 
