BBC Two until 23 October 2012, via the Ceefax teletext service. The BBC also offers audio description on some popular programmes for visually impaired-viewers as well as sign language interpretation on some of its programmes for deaf and hard-of-hearing viewers. The percentage of the BBC's total television output with audio description available is 10%, having been increased from 8% in 2008. Originally, programmes from BBC Two were shown in high definition on the dedicated BBC HD channel, alongside programmes from BBC Three and BBC Four, as well as some select series from CBBC and CBeebies. However, in plans outlined by the director
World System Teletext World System Teletext World System Teletext (or WST) is the name of a standard for encoding and displaying teletext information, which is used as the standard for teletext throughout Europe today. WST originally stems from the UK standard developed by the BBC and the UK Independent Broadcasting Authority in 1974 for teletext transmission, extended in 1976 as the Broadcast Teletext Specification. With some tweaks to allow for alternative national character sets, and adaptations to the NTSC 525-line system as necessary, this was then promoted internationally as "World System Teletext". It was accepted by CCIR in 1986 under international standard CCIR