The company uses several outside companies to let users connect with computers that run Instant Messenger and other services. Instant Messenger is available through that service, as well as for free as a stand-alone application through AOL's Web site and browsers made by its Netscape unit. AOL claims about 100 million registered users for Instant Messenger. According to Jupiter Media Metrix, more than 22 million people used the stand-alone version in April, averaging 4.2 hours. Microsoft's MSN Messenger Service came in second, at 16 million.
Instant messaging is a technique for sending quick messages to other Internet users.
Unlike e-mail, which can sit on a computer for hours or days, instant messages pop up instantly, provided the recipient is online.