Teletext

Teletext, or broadcast teletext, is a standard for displaying text and rudimentary graphics on suitably equipped <a href="/facts/Television/X4YG5nT1">television</a> sets. Teletext sends data in the broadcast signal, hidden in the invisible <a href="/facts/Vertical_blanking_interval/2lhsCf2S">vertical blanking interval</a> area at the top and bottom of the screen. The teletext decoder in the television buffers this information as a series of "pages", each given a number. The user can display chosen pages using their <a href="/facts/Remote_control/A9zmkgIV">remote control</a>.
In broad terms, it can be considered as <a href="/facts/Videotex/psxycPcf">Videotex</a>, a system for the delivery of information to a user in a computer-like format, typically displayed on a television or a <a href="/facts/Dumb_Terminal/fSlx05qV">dumb terminal</a>, but that designation is usually reserved for systems that provide bi-directional communication, such as <a href="/facts/Prestel/ov6p8pzW">Prestel</a> or <a href="/facts/Minitel/bTmoGeyh">Minitel</a>.
Teletext was created in the <a href="/facts/United_Kingdom/kuPAILt2">United Kingdom</a> in the early 1970s by John Adams, <a href="/facts/Philips/Xp4uczGg">Philips</a>' lead designer for video display units to provide closed captioning to television shows for the hearing impaired. Public teletext information services were introduced by major broadcasters in the UK, starting with the <a href="/facts/BBC/qFateIz8">BBC</a>'s <a href="/facts/Ceefax/nqVev3M9">Ceefax</a> service in 1974. It offered a range of text-based information, typically including news, weather and TV schedules. Similar systems were subsequently introduced by other television broadcasters in the UK and mainland Europe in the following years. Meanwhile, the UK's <a href="/facts/General_Post_Office/gnMB2RHN">General Post Office</a> introduced the <a href="/facts/Prestel/ov6p8pzW">Prestel</a> system using the same display standards but run over telephone lines using bi-directional <a href="/facts/Modem/9H0Xwtq0">modems</a> rather than the send-only system used with televisions.
Teletext formed the basis for the <a href="/facts/World_System_Teletext/8PknDRLm">World System Teletext</a> standard (CCIR Teletext System B), an extended version of the original system. This standard saw widespread use across Europe starting in the 1980s, with almost all televisions sets including a decoder. Other standards were developed around the world, notably <a href="/facts/NABTS/AH440L9k">NABTS</a> (CCIR Teletext System C) in the <a href="/facts/United_States/P0sCdLe5">United States</a>, <a href="/facts/Antiope_(teletext)/S6cnaz4f">Antiope</a> (CCIR Teletext System A) in <a href="/facts/France/CxIeIKM3">France</a> and <a href="/facts/JTES/sgmWQzgX">JTES</a> (CCIR Teletext System D) in <a href="/facts/Japan/U5mz0SRT">Japan</a>, but these were never as popular as their European counterpart and most closed by the early 1990s. 
Most European teletext services continued to exist in one form or another until well into the 2000s when the expansion of the <a href="/facts/Internet/Xw1rVvJU">Internet</a> precipitated a closure of some of them. However, many European television stations continue to provide teletext services and even make teletext content available via web and dedicated apps. 
The recent availability of <a href="/facts/Digital_television/KQCyILQa">digital television</a> has led to more advanced systems being provided that perform the same task, such as <a href="/facts/MHEG-5/P9MXluHL">MHEG-5</a> in the UK, and <a href="/facts/Multimedia_Home_Platform/jhd9UvfQ">Multimedia Home Platform</a>.

Teletext open-in-new

Teletext