Text messaging: that was originally designed for people who are Deaf.
Is it true?
On wired commercial networks text communication predated voice communication.
As such it was voice that was added later.
For mobile networks text communication was added on the basis of offering all the services offered in the public switched telephone networks.
The first action plan of the Group GSM was approved in December 1982, requesting that, "The services and facilities offered in the public switched telephone networks and public data networks should be available in the mobile system." This plan included the exchange of text messages either directly between mobile stations, or transmitted via message handling systems in use at that time.
Text messaging was included as part of Signalling System No. 7
It was designed to use non-voice parts of the existing protocol to carry messages in a lightweight/efficient fashion.
While useful to deaf people the first text services were for necessity since they predate voice communication and SMS on mobiles was added on the basis of giving the mobile networks the same capabilities as the wired networks.
The claim, whatever the source would appear to be false.
The TED speaker was not referring to wireless communications, but rather a telecommunications system pioneered for the deaf back in the 1960's, long before cellphones. It used older-style Teletype machines using the 5-bit Baudot code over the telephone lines and dial-up modems instead of the more modern 7-bit ASCII code used by computers and later model Teletypes. All messages were in upper-case only since lower case is not provided for in the Baudot code.
A deaf person could dial up another deaf person and establish a two-way half-duplex conversation (meaning only one could type at a time). The machines are referred to as TDDs (telecommunications devices for the deaf). The Teletypes have since been replaced by modern terminals.
The acoustic coupler is on the top. This terminal has provisions for three-way calling. It still uses the Baudout code instead of ASCII to be compatible with older devices.
Many businesses and government agencies, in additions to listing their voice and FAX numbers, also include a TDD number on their website.
A petition to the California Public Utilities Commission resulted in a tariff that paid for TTY devices to be distributed free of cost to deaf persons. The Telecommunications Accessibility Enhancement Act of 1988 established guidelines for the use of TDD in the government sector.
The deaf community came up with a number of abbreviations for use in the messages, much like today's text messaging, e.g. BRB for Be Right Back, and THX for thanks. LOL was not one of them as far as I know.
Relay services are used, in which a deaf person dials up an intermediary, and a hearing person also calls the intermediary, and the intermediary listens to the hearing person and sends a message to the deaf person and vice versa.