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
Teletext as the internet, whereby pages are 'requested' and then 'sent' to the user – a method not possible given the one-way nature of broadcast teletext. Unlike the Internet, teletext is broadcast, so it does not slow down further as the number of users increase, although the greater number of pages, the longer one is likely to wait for each to be found in the cycle. For this reason, some pages (e.g. common index pages) are broadcast more than once in each cycle. Teletext proved to be a reliable text news service during events such as the September 11 terrorist attacks,