[[Teletext]] offers one-directional data transmission, broadcast via an television signal (it is a ViewData like system).
Commonly it is found in analogue television signals and contains data for text and crude graphics. Digital televisions have text services which use a different method (almost HTML based).
Teletext is also "Mode 7" on the BBC Micro.
== Required UHF/VHF Decoder (Tuner) ==
