Board Thread:Support Requests - Community Management/@comment-17034183-20130927185532/@comment-5007040-20130929065314

To ban people: Go to the user page of the user you want to ban. Go to his contributions, click on block and follow the instructions on the block page.

To kick people from chat: You can only do this if there's somebody in the chat. Click on his avatar and you see in the list "Kick".

To ban people from chat: You can do this in the chat aswell on his contributions page. Click on his contributions page on "Ban from chat" and follow the instructions on the page.

Hope this makes it clear, but don't forget banning and kicking is not for the fun.