Telephony

n. founding and maintenance of telephone communications systems

In telecommunication, telephony (IPA pronunciation: ) encompasses the general use of equipment to provide voice communication over distances, specifically by connecting telephones to each other.Telephones originally were connected directly together in pairs. Each user had separate telephones wired to the various places he might wish to reach. This became inconvenient when people wanted to talk to many other telephones, so the telephone exchange was invented. Each telephone could then be connected to other local ones, thus inventing the local loop and the telephone call. Soon, nearby exchanges were connected together, and eventually far away ones were.
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(n.)
The art or process of reproducing sounds at a distance, as with the telephone.
  

1. The branch of science devoted to the transmission, reception, and reproduction of sounds, such as speech and tones that represent digits for signaling. Note 1: Transmission may be via various media, such as wire, optical fibers, or radio. Note 2: Analog representations of sounds may be digitized, transmitted, and, on reception, converted back to analog form. Note 3: "Telephony" originally entailed only the transmission of voice and voice-frequency data. Currently, it includes new services, such as the transmission of graphics information. 2. A form of telecommunication set up for the transmission of speech or, in some cases, other sounds. [NTIA] [RR]

<communications> Communication, often two-way, of spoken information, by means of electrical signals carried by wires or radio waves. The term was used to indicate transmission of the voice, as distinguished from telegraphy (done in Morse code and usually called "continuous wave" or CW transmission), radio teletypewriter (RTTY) transmission (also called FSK for "Frequency Shift Keying", the modulation scheme used by such machines), and later, facimile.
(1995-03-14)

Computer Telephone Integration