Stands for "Internet Relay Chat." IRC makes it possible for people using the Internet to converse with each other in real time by typing messages back and forth. In order to talk to someone through IRC, you need to connect to the same IRC server. When you and others connect to the server, you can join a channel (a.k.a. chat room), and talk with the other people who have joined that channel. Usually, channels have specific topics like "teenchat," "macusers," or "folksingingmotorcyclists." To connect to an IRC server, you'll need a software program like Ircle (Mac) or mIRC (Windows). Most IRC programs also let you transfer files with other users, which is a cool feature, but has also led to a lot of software piracy.