@Setanta,
Trolling is also, often, someone who is
deliberately (this word is important) obtuse, and continues pushing until they evoke an emotional response or otherwise disrupt things. I know that there are people who just don't get things. And it's rather difficult to determine intent online. We don't have tone, demeanor, gestures, body language, etc. to rely upon.
Still, case in point.
I belong to a bunch of writing groups online; a few are on Facebook. On one rather large one, someone asked about writing a story about Hitler winning WWII. He was really just trying to get people to donate to his Kickstarter. A number of people pointed out that such stories had been written before, and were very nearly a trope. His opening sentence was, "If Hitler had won, what would you be?"
He probably thought he was being awfully clever. So I responded, and just said, "I never would have been born."
He wrote back, "Surely, you would be a Nazi."
"No, I'm a Jew," I replied.
"Then I'll write you in my story, and you'll be the one throwing rubber ducks at Hitler!" (yes, he really wrote that)
I responded one last time, "I don't think you understand just how offensive all of this is to someone like me, and to a lot of other people."
He blithely ignored this and claimed he did understand, and then shilled some more people to fund his Kickstarter.
I was not the only person to essentially tell him to go scratch.
Bottom line, his legitimate purposes - (1) to get funding for his Kickstarter and (2) to see if there was any support out there for his basic plot idea - were overshadowed by the ham-handed way he went about things. Plus he completely ignored the fact that someone had a legitimate gripe and a legitimate reason for being offended. He further ignored the very real fact that writers generally don't want to be written into others' stories without permission (because we know what we do to characters).
Far as I'm aware, his Kickstarter failed, so it's a moot point anyway, but this was a case of, I feel, deliberate obtuseness with an intention to get me and others to blow our stacks. I think that's the important takeaway, that the inability to get something is
deliberate, often pushing the other person(s) to continue explaining until the others are exasperated. It's often a push to get others to lose their tempers.
What was the solution?
We ignored him.
Wikipedia wrote:In Internet slang, a troll (/ˈtroʊl/, /ˈtrɒl/) is a person who sows discord on the Internet by starting arguments or upsetting people, by posting inflammatory, extraneous, or off-topic messages in an online community (such as a forum, chat room, or blog), either accidentally or with the deliberate intent of provoking readers into an emotional response or of otherwise disrupting normal on-topic discussion.
http://en.wikipedia.org/wiki/Internet_troll