The ability to send instant text messages over computers was introduced to the public in 1996. Internet service provider America Online (AOL) launched instant messaging, or IM, as another way for its members to communicate with each other. By logging onto a home or work computer (or cell phone with Internet capabilities), users could view their “buddy list” and see which of their AOL contacts were online at the time. IM users could then send messages back and forth in real time, next door or across thousands of miles. In 1997 AOL expanded the service to non-AOL users with a utility called AOL Instant Messaging (AIM), and in 1998 the company acquired another IM utility, ICQ. By 1999 MSN and Yahoo rolled out their instant messenger services, and others followed. The concept caught on, particularly with young users who embraced the concept of a private chat room. In 2004 a Pew Internet and American Life Project report estimated that 53 million Americans, or 4 out of 10 Internet users, were instant messaging. IM had become the primary form of communication for many, replacing telephone calls and emails. The mode of communication also brought about a new shorthand, or subculture language, with a heavy reliance on abbreviations and icons. The use of the technology continued to grow rapidly, expanding to practical business use. In 2004 analysts estimated that there were about 600 million registered IM users worldwide.