How to view chat webcams?

I use the IM a lot and chat one on one via the member directory but have not spent any time in the chat rooms due to all the commercial stuff. What little time I have been there I notice some chatters with a t.v. looking box beside their name. Does this mean they are using their webcam? I see everyone asking about webcams but don’t you need someones permission to view their cam or if it is available to all is there a way to tell? Then what do you do just click on it? Is there a way to view random cams? Thanks.