IRC (Internet Relay Chat) is a worldwide, free, internet-based chatroom system. Unlike person-to-person instant messenger, IRC allows a very large number of people to communicate with each other simultaneously. It is therefore very popular with hobbyists, academics, software developers and hackers. It is, effectively, the CB radio of the internet.
IRC is not "owned" by any particular company. It is an open protocol, and the infrastructure that supports it is operated entirely by volunteers and donations. If you have an internet connection, you can use IRC.
#pirateradio is an IRC channel dedicated to monitoring and discussion of pirate radio stations. It is known for attracting a diverse and interesting cross-section of the community. There is activity on the channel almost every night, including pirate radio listeners from North America and Europe. Some regulars include Chris Smolinski, Beerus Maximus, Al Fansome and Kracker.
To use IRC, you must download and install a client on your computer. Using this client, you connect to an IRC server and then join a "channel" . For some historical reason, all channel names begin with the "#" (pound) character. Therefore, the name of the channel to join for pirate radio activity is #pirateradio. Because IRC is an open protocol, there are many options for client software. Almost all of them are free.
Status Update - October 26, 2007: the "official" #pirateradio channel is the one on StarChat. The zIRC network is currently down, and it is not know if it will be coming back. Please try connecting to the StarChat #pirateradio channel first.