less_retarded_wiki/teletext.md
Miloslav Ciz f0c3f6aecf Update
2022-05-18 21:18:17 +02:00

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# Teletext
Teletext is now pretty much obsolete technology that allowed broadcasting extremely simple read-only text/graphical pages along with TV signal so that people could browse them on their [TVs](tv.md). It was used mostly in the 70s, 80s and 90s but with [world wide web](www.md) teletext pretty much died.
{ Just checked on my TV and it still works in 2022 here. For me teletext was something I could pretend was "the internet" when I was little and when we didn't have internet at home yet, it was very cool. Back then it took a while to load any page but I could read some basic news or even browse graphical logos for cell phones. Nowadays TVs have buffers and have all the pages loaded at any time so the browsing is instantaneous. ~drummyfish }
The principal difference against the [Internet](internet.md) was that teletext was [broadcast](broadcast.md), i.e. it was a one-way communication. Users couldn't send back any data or even request any page, they could only wait and catch the pages that were broadcast by TV stations (this had advantages though, e.g. it couldn't be [DDOSed](ddos.md)). Each station would have its own teletext with fewer than 1000 pages -- the user would write a three place number of the page he wanted to load ("catch") and the TV would wait until that page was broadcast (this might have been around 30 seconds at most), then it would be displayed. The data about the pages were embedded into unused parts of the TV signal.
The pages allowed fixed-width text and some very blocky graphics, both could be colored with very few basic colors. It looked like something you render in a very primitive [terminal](terminal.md).