How do you make a forum private?

[Priya]

I've noticed that other forums make their site private so that you can't see the threads unless your registered. In other words i do not want guests coming and going and taking material from my forum unless they're registered. Can someone tell me how to make the forum private and whether this is possible or not?

[Shadow]

Forum > forum permissions control > click the category you wish to make private > uncheck all guests possibilities.
Do the same for each category