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Description

Homepage: http://xmpp.org/about/
Type: Open standard
Identity: Jabber ID (JID), e.g. usr@a.b.c/home with "home" being a "resource", which distinguishes the same user when logged in from multiple locations (simultaneously)
Interoperability: Google Talk, LiveJournal

Unlike traditional and proprietary instant messaging services, with XMPP (previously known as "Jabber") there is no central server. Similar to email, users can choose a server and they will be able to communicate with users connected to a different XMPP server. In fact, everybody (with a static IP) can host an XMPP server of their own, optionally linking it up to the global XMPP network (otherwise, only local users on the same server are accessible).

There are already several larger XMPP installations, like Google Talk and LiveJournal.

Further information:

History

Censorship