4chan?

I visited 4chan, i've seen some suff I shouldn't have, I googled it, and everything, but I still can not figure out what is it for. Why are people telling each other off anonymously? Or is it just overloaded with trolls, and I didn't see behind them? or what? Maybe if people would be a bit more civilised over there, it wouldn't be blocked?

Sorry, if I hurt anyone's feelings, I'm not trying to say anything good or bad about it, because I don't know it enough to judge, but the first impression kind of explained why would someone block it.

Is there anything I should know? (besides what I read on wikipedia, and Encyclopedia Dramatica)

4chan is for superior beings, not afraid of pictures or reality.
Political correctness is banished here. There is enough of this shit in real life already.
If you can't stand a 300*250 pic of a smashed head, go away, go back to your well controlled "acceptable" shitty opinion sites populated with polite people who will get you banned if you say something a little too harsh.