World System Teletext 653 (now ITU-R BT.653) as one of four recognised standards for teletext worldwide, and may now most commonly be referred to as CCIR Teletext System B. Almost all television sets sold in Europe since the early ’80s have built-in WST-standard teletext decoders as a feature. WST is used for all teletext services in Europe & Scandinavia, including Ceefax from the BBC and services from Teletext on ITV in the United Kingdom, ZDFtext from ZDF and ARDText from ARD in Germany, and Tekst-TV from NRK in Norway, among many other teletext services offered by other television networks throughout the European continent.
Teletext list of news headlines might appear on page 110; a teletext user would type "110" into the TV's remote control to view this page. The broadcaster constantly sends out pages in sequence. There will typically be a delay of a few seconds from requesting the page and it being broadcast and displayed, the time being entirely dependent in the number of pages being broadcast. More sophisticated receivers use a memory buffer to store some or all of the teletext pages as they are broadcast, allowing instant display from the buffer. This basic architecture separates from other digital information systems, such