History

Instant messaging actually predates the Internet, first appearing on multi-user operating systems like CTSS and Multics[1] in the mid-1960s. Initially, many of these systems, such as CTSS'.SAVED, were used as notification systems for services like printing, but quickly were used to facilitate communication with other users logged in to the same machine. As networks developed, the protocols spread with the networks. Some of these used a peer-to-peer protocol (eg talk, ntalk and ytalk), while others required peers to connect to a server (see talker and IRC). During the BBS phenomenon that peaked during the 1980's, some systems incorporated chat features which were similar to instant messaging. Freelancin'_Roundtable was one prime example.

In the last half of the 1980s and into the early 1990s, the Quantum Link online service for Commodore 64 computers offered user-to-user messages between currently connected customers which they called "On-Line Messages" (or OLM for short). Quantum Link's better known later incarnation, America Online, offers a similar product under the name "AOL Instant Messages" (AIM). While the Quantum Link service ran on a Commodore 64, using only the Commodore's PETSCII text-graphics, the screen was visually divided up into sections and OLMs would appear as a yellow bar saying "Message From:" and the name of the sender along with the message across the top of whatever the user was already doing, and presented a list of options for responding.[2] As such, it could be considered a sort of GUI, albeit much more primitive than the later Unix, Windows and Macintosh based GUI IM programs. OLMs were what Q-Link called "Plus Services" meaning they charged an extra per-minute fee on top of the monthly Q-Link access costs.

Modern, Internet-wide, GUI-based messaging clients, as they are known today, began to take off in the mid 1990s with ICQ (1996) being the first, followed by AOL Instant Messenger (AOL Instant Messenger, 1997). AOL later acquired Mirabilis, the creators of ICQ. A few years later ICQ (by now owned by AOL) was awarded two patents for instant messaging by the U.S. patent office. Meanwhile, other companies developed their own applications (Excite, MSN, Ubique, and Yahoo), each with its own proprietary protocol and client; users therefore had to run multiple client applications if they wished to use more than one of these networks. In 1998 IBM released IBM Lotus Sametime, a product based on technology acquired when IBM bought Haifa-based Ubique and Lexington-based Databeam.

In 2000, an open source application and open standards-based protocol called Jabber was launched. Jabber servers could act as gateways to other IM protocols, reducing the need to run multiple clients. Modern multi-protocol clients such as Pidgin, Trillian, Adium and Miranda can use any of the popular IM protocols without the need for a server gateway. IBM Lotus Sametime's November 2007 release added IBM Lotus Sametime Gateway support for XMPP.

Recently, many instant messaging services have begun to offer video conferencing features, Voice Over IP (VoIP) and web conferencing services. Web conferencing services integrate both video conferencing and instant messaging capabilities. Some newer instant messaging companies are offering desktop sharing, IP radio, and IPTV to the voice and video features.

The term "instant messenger" is a service mark of Time Warner[3] and may not be used in software not affiliated with AOL in the United States. For this reason, the instant messaging client formerly known as Gaim or gaim announced in April 2007 that they would be renamed "Pidgin"[4].