Question

What happens when I block someone?

Answer 1

They can't message you or fan you.
I think they can still tag you, but I'm not sure.

Answer 2

So there is no way to get rid of people that waste and span your thread tick you off and etc?

Answer 3

Not unless a mod deletes their posts.
If they spam your question, report them.

Answer 4

I blocked the person that kept annoying me, and it is just a message block for the blocker and the blocked, accept that the blocker could message after unblocking and the blocked has to wait untill the blocker unblocks him.
So the blocker decides basically.