Trolls are what folks in my day used to call assholes. Trolling isn't just joking with your buddies about something innocuous. It has become an excuse for just being a jerk to people and hoping they don't pop you in the nose. On the other hand there are genuine good pranksters whose craft is finely honed and deserving of appreciation.

Of course that in this context it's the latter just as anigbrowl's comment proves.

Yes, because attacking people and bullying them is a wonderful way to make friends and influence people.

I think s/he means the type of trolling where you pretend to be monumentally stupid to see whether other people catch on, eg 'what do you mean the world isn't flat, I've been up in a plane so don't think you're fooling me with that round nonsense.'

I don't go in for this but I do find it entertaining to read sometimes.