(1) (MicroSoft Network) A family of Internet-based services from Microsoft, which includes a search engine, e-mail (Hotmail), instant messaging (Windows Live Messaging) and a general-purpose portal with news, information and shopping (MSN Directory).

In concert with Windows 95, MSN was launched in 1995 as an online service with proprietary content similar to AOL. It later included Internet access and became a major player in the U.S. ISP hosting market. For more information, visit www.msn.com. See Windows Live.

(2) Short for MSN Messenger, the instant messaging service from MSN. MSN Messenger became Windows Messenger in Windows XP and then Windows Live Messenger. See MSN Messenger and Windows Live Messenger.