Windows Live Messenger (formerly named MSN Messenger) is an instant messaging client created by Microsoft that is currently designed to work with Windows XP, Windows Vista, Windows 7, Windows Mobile/Windows CE, Xbox 360, Blackberry OS, iOS, Java ME, S60 on Symbian OS 9.x and Zune HD. The client has been part of Microsoft’s Windows Live set of online services since 2005. It connects to Microsoft’s .NET Messenger Service. The client was first released as MSN Messenger on July 22, 1999, and as Windows Live Messenger on December 13, 2005. In June 2009, Microsoft reported the service attracted over 330 million active users each month.

Size : 1.12 MB

Yahoo! Messenger is an advertisement-supported instant messaging client and associated protocol provided by Yahoo!. Yahoo! Messenger is provided free of charge and can be downloaded and used with a generic “Yahoo! ID” which also allows access to other Yahoo! services, such as Yahoo! Mail, where users can be automatically notified when they receive new email. Yahoo! also offers PC-PC, PC-Phone and Phone-to-PC service, file transfers, webcam hosting, text messaging service, and chat rooms in various categories.

Yahoo! Messenger was originally launched under the name Yahoo! Pager on March 9, 1998.

In addition to instant messaging features similar to those offered by ICQ, it also offers (on Microsoft Windows) features such as: IMVironments (customizing the look of Instant Message windows, some of which include authorized themes of famous cartoons such as Garfield or Dilbert), address-book integration and Custom Status Messages. It was also the first major IM client to feature BUZZing and music-status. Another recently added feature is customized avatars.

Size : 16.8  MB