What is IRC?
It's short for Internet Relay Chat, a client-server based chat system. Only a year younger than the current guildmaster, it's one of the first client-server-based webchats in the internet. The server is hosted by mana and you can connect with a client.
I don't have a client!
You can use the webclient, or find a preconfigured client with a sample picture of how to configure it here. (It will make nirnroot noises when you need to tab in!)
Or you can throw "IRC client" into google and check out what's out there - hexchat works fine, for example.
There are even mobile clients. For iphone I recommend IRCCloud, for Android I use AndroIRC myself.
What can it do?
- use it to chat
- register your nickname by typing /ns register password email, then set the password in your client or sign in via /ns identify password
- group more nicknames to your main nickname by /ns group yourmainnick password
- join or create channels by typing /join #channel
- whisper people by typing /msg nickname
- emote by writing /me does something
... and much more.