Talkomatic

Talkomatic (http://talko.cc/) is an online chat system that facilitates real-time text communication among a small group of people. It is distinguished from most online chat facilities in that each participant appears in their own section of the screen, and messages are broadcast letter-by-letter as they are typed. Most chat systems transmit a message only after the sender has indicated that the message is complete.

The original Talkomatic was the world's first multi-user online chat system, with the possible exception of the Party Line function of the Emergency Management Information Systems And Reference Index (EMISARI) system, created for the US Office of Emergency Preparedness by Murray Turoff in 1971 . Talkomatic was created by Doug Brown and David R. Woolley in 1973 on the PLATO System at the University of Illinois. It offered six channels, each of which could hold up to five participants. Along with PLATO Notes and a wide variety of games, Talkomatic was one of the features of PLATO that gave rise to a large online community that persisted into the mid 1980s.

Ray Ozzie's smartphone app, Talko, launched in September 2014, is named after Talkomatic, which Ozzie experienced while working on the PLATO System in the 1970s.

In March 2014, Brown and Woolley released a new version of Talkomatic designed for the world wide web. In its basic functionality it is very similar to the original Talkomatic, but it is based on entirely different technology. It offers an unlimited number of rooms, which can be either public or private. Each room can accommodate up to five people.

...
Wikipedia