Jabber is an open-source instant messaging structure based upon XML protocols. Now stop putting stupid things in the 'jabber' field on your user information pages, folks: it's the "O RLY" of Livejournal now.
AD: Okay, I guess I was a little too tough here. I realize most people don't touch their userinfo pages for years at a time. I also don't mean to be disrespecting Mr. T, either. Still, my sentiment stands intact: Jabber, like Mr. T, deserves some respect.