Editing Videotex (section)

=== United Kingdom ===
The first attempts at a general-purpose videotex service were created in the [[United Kingdom]] in the late 1960s. In about 1970 the [[BBC]] had a brainstorming session in which it was decided to start researching ways to send [[closed captioning]] information to the audience. As the Teledata research continued the BBC became interested in using the system for delivering any sort of information, not just closed captioning.
In 1972, the concept was first made public under the new name [[Ceefax]]. Meanwhile, the [[General Post Office]] (soon to become [[British Telecom]]) had been researching a similar concept since the late 1960s, known as [[Viewdata]].<ref>{{cite web| url=http://aei.pitt.edu/94572/1/videotex.pdf | title=Videotex in Europe | access-date=2023-12-27}}</ref> Unlike Ceefax which was a one-way service carried in the existing TV signal, Viewdata was a two-way system using telephones. Since the Post Office owned the telephones, this was considered to be an excellent way to drive more customers to use the phones. Not to be outdone by the BBC, they also announced their service, under the name [[Prestel]]. ITV soon joined the fray with a Ceefax-clone known as [[ORACLE (teletext)|ORACLE]].

In 1974, all the services agreed on a standard for displaying the information. The display would be a simple 40×24 grid of text, with some "graphics characters" for constructing simple graphics, revised and finalized in 1976.<ref>{{Cite web|url=http://www.doc.ic.ac.uk/%7Eih/teaching/teletext/tt-spec/|title=Broadcast Teletext Specification, September 1976}}</ref> The standard did not define the delivery system, so both Viewdata-like and Teledata-like services could at least share the TV-side hardware, which was expensive at the time. The standard also introduced a new term that covered all such services, [[teletext]]. Ceefax first started operation in 1974 with a limited 30 pages, followed quickly by ORACLE and then Prestel in 1979.

By 1981, Prestel International was available in nine countries, and a number of countries, including Sweden, The Netherlands, Finland and West Germany were developing their own national systems closely based on Prestel. [[General Telephone and Electronics]] (GTE) acquired an exclusive agency for the system for North America.

In the early 1980s, videotex became the base technology for the London Stock Exchange's pricing service called TOPIC. Later versions of TOPIC, notably TOPIC2 and TOPIC3, were developed by Thanos Vassilakis and introduced trading and historic price feeds.<ref>Business Information at Work
By Michael Lowe, 1999, Routledge.</ref><ref>The videotex marketplace: A theory of evolution
Author links open overlay panel. James A.Campbell, Hilary B.Thomas</ref>