Up until 2000, IM users had no choice but to run multiple IM applications to access friends across different networks. That is, until Jabber changed the rules.
Known as a multi-protocol IM, Jabber united the IMs by acting as a single gateway to accessing multiple IM clients at once. Users of such clients could now simultaneously chat with friends on their AIM, Yahoo! and MSN contact lists within a single application. Other multi-protocol clients include Pidgin, Trillian, Adium and Miranda.

