windows live messenger
Windows Live Messenger is the instant messaging client made by Microsoft to serve as an alternative to the wildly popular instant messaging programs AIM (made by AOL) and ICQ. Originally called MSN Messenger, which was bundled with the MSN internet service, the program was renamed when Microsoft rebranded its core online presence as part of its Live services.
The program has seen a rebirth as it was integrated into Microsoft's Xbox 360 gaming platform to serve as the in-game chatting service (via text or voice) for the online gaming feature Xbox Live.
As of 2006, Windows Live Messenger enjoyed a 61% worldwide instant messaging (IM) market share.