What is IRC?

Internet Relay Chat (IRC) is a form of real-time Internet text messaging (chat) or synchronous conferencing. It is mainly designed for group communication in discussion forums, called channels, but also allows one-to-one communication via private message as well as chat and data transfers via Direct Client-to-Client.

Where can I get an IRC client?

There are a multitude of free IRC clients available on the web: For a full listing of clients and a comparison of their features, visit the IRC client comparison page on Wikipedia.

Also, Osiris have an IRC client in the main UI interface.