The first chat system was used by the U.S. government in 1971. It was developed by Murray Turoff, a young PhD graduate from Berkeley, and its first use was during President Nixon's wage-price freeze under Project Delphi. The system was called EMISARI and would allow 10 regional offices to link together in a real-time online chat known as the party line. It was in use up until 1986. The first public online chat system was called
Talkomatic, created by Doug Brown and David R. Woolley in 1973 on the
PLATO System at the
University of Illinois. It offered several channels, each of which could accommodate up to five people, with messages appearing on all users' screens character-by-character as they were typed. Talkomatic was very popular among PLATO users into the mid-1980s. In 2014 Brown and Woolley released a web-based version of Talkomatic.
The first dedicated online chat service that was widely available to the public was the CompuServe
CB Simulator in 1980, created by
CompuServe executive Alexander "Sandy" Trevor in
Columbus, Ohio. Chat rooms gained mainstream popularity with
AOL.
Jarkko Oikarinen created
Internet Relay Chat(IRC) in 1988.
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