Videotex

Minitel was possibly the world's most successful videotex service. This Minitel 1 terminal was one of the first devices to connect to the Minitel.

Videotex was one of the first to implement an end-user information system. Beginning in the late 1970s through the early 2010s, it was used to deliver information (usually pages of text) to users in computerized form, typically displayed on a television set or computer terminal .

In a strict definition, videotex is any system that provides interactive content and displays it on a screen, such as a television set, and typically uses modems to send data in both directions. A close relative is teletext , which sends data in only one direction, usually included in the television signal. Unlike the modern internet, the traditional videotex systems were heavily centralized.

Names and standards in different countries

It was actually intended by the CEPT to coordinate the developments that diverged at the national level. According to the British and French standards, a Swedish standardization proposal expanded the British PRESTEL with an expanded set of finer mosaic graphic characters, while the specification of the intended German screen text system, which was developed by IBM for the Deutsche Bundespost , made use of all other standards and made its own extensions . BTX was used in May 1981 as the basis for CEPT recommendation T / CD 06-01. However, due to national pressure, the CEPT did not leave it at setting a single standard, but recognized four profiles :

• CEPT-1, which corresponds to the German BTX (from 1990 also marketed in Spain by Telefónica as Ibertex )
• CEPT-2, the French Minitel
• CEPT-3, the British PRESTEL
• CEPT-4, the Swedish Prestel Plus

The national videotex services were encouraged to follow one of the four existing profiles of the CEPT standard, or if they expanded them, to do so in a way that was compatible.

Other European countries used a mixture of the four existing profiles for their own networks.

Individual evidence

1. ↑ The viewdata war is over , New Scientist , May 14, 1981, English
2. ↑ ETS 300 072, Terminal Equipment: Videotex presentation layer protocol: Videotex presentation layer data syntax , November 1990. Updated version of the CEPT recommendation T / CD 06-01, English
3. ↑ For example Main events and developments in the electronic information services market 1991 (PDF) , Report of the European Commission COM (93) 156. See Table 14, page 30 (page 39 of the PDF file)