Real-time text

Real-time text (RTT) is text transmitted instantly as it is typed or created. Recipients can immediately read the message while it is being written, without waiting.

Real-time text is used for conversational text, in collaboration, and in live captioning. Technologies include TDD/TTY devices for the deaf, live captioning for TV, a feature enhancement in instant messaging, captioning for telephony/video teleconferencing, telecommunications relay services including ip-relay, transcription services including Remote CART, TypeWell, collaborative text editing, streaming text applications, next-generation 9-1-1/1-1-2 emergency service. Obsolete TDD/TTY devices are being replaced by more modern real-time text technologies, including ip-relay and instant messaging.

During 2012, the Real-Time Text Taskforce (R3TF) designed a standard international symbol to represent real-time text, as well as the alternate name Fast Text to improve public education of the technology.

While standard instant messaging is not real-time text (the message is only sent at the end of a thought, not while it is being composed), a real-time text option is found in some instant messaging software, including AOL Instant Messenger's "Real-Time IM" feature. Real-time text is also possible over any compatible chat networks, including those used by Apple iChat, Cisco WebEx, and Google Talk, by using appropriate software that has a real-time text feature. When present in IM programs, the real-time text feature can be turned on/off, just like other chat features such as audio. Real-time text programs date at least to the 1970s, with the talk program on the DEC PDP-11, which remains in use on Unix systems.

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