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, Text over IP (ToIP), some types of 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^[1] emergency service. Obsolete TDD/TTY devices are being replaced by more modern real-time text technologies, including Text over IP, ip-relay, and instant messaging.