Teletypewriter (TTY)

Technologies that provide communication assistance to the deaf have continued to develop over time. As with the teletypewriter (TTY), these devices may be designed specifically for the deaf, or as with the fax, they may be used by the deaf even if they were not designed with this intention. The TTY originally resembled a small typewriter that had been enhanced with a standard telephone cradle and receiver. Communication by TTY is available only when both the sending and receiving parties have access to a TTY device. The sender types a message on the keyboard of the device, which then transmits it along a telephone relay system via an operator who dials a telephone number. The operator may also communicate with either party when necessary.

In 1964, ...