Picturephone

The history of videotelephony covers the historical development of several technologies which enable the use of live video in addition to voice telecommunications. The concept of videotelephony was first popularized in the late 1870s in both the United States and Europe, although the basic sciences to permit its very earliest trials would take nearly a half century to be discovered. This was first embodied in the device which came to be known as the video telephone, or videophone, and it evolved from intensive research and experimentation in several telecommunication fields, notably electrical telegraphy, telephony, radio, and television.

The development of the crucial video technology first started in the latter half of the 1920s in the United Kingdom and the United States, spurred notably by John Logie Baird and AT&T's Bell Labs. This occurred in part, at least with AT&T, to serve as an adjunct supplementing the use of the telephone. A number of organizations believed that videotelephony would be superior to plain voice communications. However video technology was to be deployed in analog television broadcasting long before it could become practical—or popular—for videophones.

Videotelephony developed in parallel with conventional voice telephone systems from the mid-to-late 20th century. Very expensive videoconferencing systems rapidly evolved throughout the 1980s and 1990s from proprietary equipment, software and network requirements to standards-based technologies that were readily available to the general public at a reasonable cost. Only in the late 20th century with the advent of powerful video codecs combined with high-speed Internet broadband and ISDN service did videotelephony become a practical technology for regular use.

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