Privacy issues that may occur with using IM and chat rooms.
InsTANT Messaging
Just like email you can be a target for spam on instant messaging. Also, if you share and copy files and send it to a friend on instant messaging that file could have a virus on it and your friends computer could now get it too. Your conversations on IM could be logged and seen by someone you're chatting with or even by the IM service provider, the privacy of your conversations or such things online can never be safe for sure.
Chat Rooms
Since chat rooms are so anonymous this is the perfect place where online predators go. You only know a screen name so anyone could make up fake information about themselves to try to get close to you or get private information out of you that you shouldn’t be sharing. Also, since everything is anonymous people think they may be aloud to say rude, sexual and insulting comments because no one knows who you are.