TELETEXT
Teletext
Teletext is a television information retrieval service created in the United Kingdom in the early 1970s by the Philips Lead Designer for VDUs, John Adams. Teletext is a means of sending text and diagrams to a properly equipped television screen by use of one of the vertical blanking interval lines that together form the dark band dividing pictures horizontally on the television screen. It offers a range of text-based information, typically including news, weather and TV schedules. Subtitle information is also transmitted within the television signal. The first test transmissions were made by the BBC in 1973, known as Ceefax . After adoption in the UK the standards ...The above text is a snippet from Wikipedia: Teletext
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