Each has its own strengths and weaknesses. It's their version of a malt shop. Chat rooms allow many people to interact with each other in real time. Part of the fascination is the amazing variety of people you encounter in chat rooms. You'll find some regulars, but most dip in for a few minutes to see what kind of conversation may be going on, and then drop out to find another chat room.
Users commonly give aliases rather than their real names.
Conversations can seem pretty disjointed, too, since there's a lag time of 30 seconds or so between a question the time it takes the other person to type out an answer and send it to the chat room. If two or three conversations are going on at once, it can look pretty scattered. While most conversations seem pretty inane, you sometimes find people that are dealing with real issues and looking for help. For them, chat can be an introduction to the Christian gospel. A second kind of real-time chat tool is called instant messaging.