IRC (Internet Relay Chat) provides a way of communicating in real time with people from all over the world. It consists of various separate networks (or "nets") of IRC servers, machines that allow users to connect to IRC.
Generally, the user (such as you) runs a program (called a "client") to connect to a server on one of the IRC nets. The server relays information to and from other servers on the same net. Recommended clients:
Be sure to read the documentation for your client!
Once connected to an IRC server on an IRC network, you will usually join one or more "channels" and converse with others there. On amiria, there are several channels, each devoted to a different topic. Conversations may be public (where everyone in a channel can see what you type) or private (messages between only two people, who may or may not be on the same channel). IRC is not a "game", and I highly recommend you treat people you meet on IRC with the same courtesy as if you were talking in person or on the phone, or there may be serious consequences.