IRC is Internet Relay Chat. It is an extremely popular chat system, first set up in Finland in 1988 by Jarkko Oikarinen. To connect to IRC you need to use an IRC client. This is the program through which you conduct all IRC activities. Think of it as being simlar to a Web Browser but instead of viewing websites with it you view IRC channels.
Chats take place in Channels .
A channel can be though of as a chat room - everyone in the channel can see everything everyone else types. The first thing you should do is get hold of an IRC client. Once you've downloaded the file you need to run it - it's a self extracting .exe file so all you need to do is tell it a directory to install into. One you've installed it you can run mIRC for the first time. Click the 'Add' Button and you will be returned to the previous Options Screen.