Yours, Etc.: Origins and Uses of 8 Sign-Offs
(PTT) One of the many national bodies responsible for providing communications services in a particular country. Traditionally, PTTs had monopolies in their respective countries. This monopoly was first broken in the USA, with the UK joining somewhat later. Currently the markets are being deregulated in Europe as well as other parts of the world.
Well-known PTTs include MCI, AT&T, and British Telecom.