How to get started with IRC
If you're reading this you're probably new to IRC. I was new too, so I'll try to help you.
IRC is pretty simple - it's a system to talk to people online instantly - just like instant messaging like AIM, gtalk (aka Jabber), or MSN. It's commonly used to talk to a bunch of people at once, and that's how sugar labs uses it as well.
Just like with instant messaging, you can use software that runs on your computer or through a website.
There's a list of IRC clients that you can install and run on your computer here: http://en.wikipedia.org/wiki/Comparison_of_Internet_Relay_Chat_clients
I have only used XChat and Colloquoy