Teletext default graphics mode (mode 7) was based on Teletext display, and the computer could be used to create and serve Teletext-style pages over a modem connection. With a suitable adapter, the computer could receive and display teletext pages, as well as software over the BBC's Ceefax service, for a time. The Philips P2000 home computer's video logic was also based on a chip designed to provide teletext services in TVs. Prestel was a British information-retrieval system based on teletext protocols. However, it was essentially a different system, using a modem and the phone system to transmit and receive the data,
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,