Internet Relay Chat (IRC) has long
been a popular way for many people to get together online to chat all
at once. The way that it works is simple: you log on to a chat server,
join a chat room (or channel), and every message entered by a person in
that room is broadcast to everyone else in the same room.
Chat servers must belong to a chat network, such as EFnet (the
original IRC network), Undernet, and DALnet. All chat channels on a particular
network are relayed to all the other servers connected to the same network
(hence the name Internet Relay Chat).
You can easily recognize a chat channel by the # symbol before
the name of the channel (for example, #chat). The name of the channel
will usually give a good indication about the main topic of discussion
on that channel. For instance, the channel #music-videos is devoted to
discussing music videos, naturally.
A chat client is the software you use to access the IRC server,
and most chat clients are designed to permit a lot more than simply
relaying chat text. IRC clients can also log (record) chat sessions,
send private messages, and even send and receive files to other users