Teletext systems expensive cost of NABTS decoders, costing in the thousands of dollars upon their release to the public. NABTS, however, was adopted for a short while by American TV networks NBC & CBS throughout the early-to-mid 80s, CBS using it for their short-lived ExtraVision teletext service, which premiered after the early Antiope & Ceefax trials by CBS & KNXT, and NBC, who had a NABTS-based service called NBC Teletext for a very short time in the mid-1980s. NBC discontinued their service in 1985 due to the cost of NABTS decoders not dropping to an affordable level for the consumer public. The
Teletext during which the webpages of major news sites became inaccessible because of the high demand. Teletext is also used for carrying special packets interpreted by TVs and video recorders, containing information about subjects such as channels and programming. Although the term "teletext" tends to be used to refer to the PAL-based system, or variants, the recent availability of digital television has led to more advanced systems being provided that perform the same task, such as MHEG-5 in the UK, and Multimedia Home Platform. Teletext is a means of sending text and simple geometric shapes to a properly equipped television screen