With its crude graphics and agonizingly slow-loading pages, Teletext is probably remembered by most today - if at all - as a quaint relic of a bygone era. But the BBC's Ceefax and ITV's Oracle were a fixture in millions of homes for nearly 40 years.

This short video, made for the Department of Trade and Industry by the Central Office of Information, uses mock razzle-dazzle marketing techniques - tongue-in-cheek, but not entirely so - to convince television sales workers to get on board the coming revolution, because, insists our slick salesman, 'in a few years' time [Teletext is] going to seem a domestic necessity, just like running water'.

What's striking about this video - and about other claims made for Teletext in its early days - is how much of it could be describing the World Wide Web (at this point still nearly two decades away). The arrival of Teletext, we're told, 'puts the vast information-gathering resources of the television networks literally on tap: you tap out the page, and you get the information.' In the way it transforms our television sets, this new technology marks 'the big jump from passive to active, from snoozer to user.'

Like television, as the video is proud to claim, Teletext was a British innovation (as, of course, was the World Wide Web). But though it was enjoyed by millions, it never became as central to national life in the way that France's Minitel did. Curiously, the one feature that really did change many users' lives doesn't get a mention here. The first 'closed caption' subtitles were introduced on Ceefax in 1979, with Oracle not far behind. Only a handful of programmes were subtitled at first, but for deaf and hearing-impaired viewers, page 888 (where subtitles eventually ended up) opened the door to a new era of television.