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videotex, communications service that is linked to an adapted television receiver or a personal computer by telephone lines, cable television facilities, or the like, and that allows a user to retrieve and display alphanumeric and pictorial information at home. Traditional videotex systems are limited to menu-oriented applications, in which information is selected from hierarchically arranged menus and displayed in fixed frames. Newer technologies allow greater interactivity and scroll the information across the viewing screen. There are two forms of videotex systems. One-way teletext systems permit the selection and display of such general information as airline schedules, traffic conditions, and traditional newspaper content. Viewdata systems are more specific and provide for two-way, or interactive, communication. Specific questions may be researched by accessing the appropriate database: e.g., bank balances can be verified and bills paid, merchandise can be ordered from retail merchants and catalogs, and travel and hotel reservations can be made.
In Japan and Europe, government-operated videotex systems : among them Captain in Japan, Prestel in Britain, Bildschirmtext in Germany, and Minitel in France : are well established. In North America, systems have been developed by newspaper publishers (called electronic news) and banks. With the growing popularity of the personal computer, particularly in the United States, database services : called on-line systems or interactive services : are becoming more significant. These make the home user part of an interactive network and provide electronic mail and bulletin board facilities in addition to traditional videotex services. On-line systems also serve as gateways to the Internet, giving the user access to facilities worldwide. A growing trend, primarily in the United States and Canada but also in New Zealand and Finland, is the public computer system, modeled after public radio and public television systems. The first publicly supported computer system was the Heartland Freenet in Peoria, Ill.; by the mid 1990s more than two dozen other cities had free computer utilities containing community-oriented information and operated by universities or local governments.
See A. F. Alber, Videotex/Teletext: Principles and Practices (1985); P. L. Mothersole and N. W. White, Broadcast Data Systems (1990); A. F. Alber, Interactive Computer Systems: Videotex and Multimedia (1993).
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