Past, present, future
But in terms of education, in the privacy of your own classroom, you can already see the first steps being taken by broadcasters towards the fabled information superhighway. At the heart of John Birt's vision of a digital future for broadcasting is the concept of "convergence", in which the technologies of television and computing merge, producing multimedia systems that combine moving images, text and interactive services.
Already, if you have an Internet connection, you can visit BBC Education's site and find the beginnings of an integrated on-line service to schools. All the BBC's schools programmes are indexed here, and with a click on a programme title, you can have access to background information, supporting materials, links to the curriculum and cross-references to any other relevant schools television series.
If you want advice on using the programme, the Internet site has links to the BBC's education officers, who can be sent e-mail questions directly from the information pages for the price of a phone call.
From information directly linked to schools series, the Internet service allows you to step sideways into other related fields. So, for instance, if you looked up the material on English File, you could move to a database of information about Charles Dickens or find a chronology of the life of Coleridge. There are huge archives of classic literary texts on-line, which can be searched or downloaded on to your own computer.
All that's missing from this BBC Education package are the television and radio programmes themselves. At present, the ordinary phone lines that most people use to reach the Internet lack the capacity to be able to carry video images - trying to send a television picture through the Internet would have the same effect on your computer as trying to eat your own body weight in porridge. But the technologists promise that with fibre-optic cable all this could change.
Already the first flickering moving images carried by the Internet have appeared on sites such as that provided by news channel, CNN. From here you can download a few seconds of news footage, which you can save on your computer's hard disc.
Channel 4 also has an Internet site supporting its schools television series, with background information and ideas for using the programmes. This too has the potential to offer teachers a great stack of supporting information in one single site.
The BBC's Internet address is http:www.bbcnc.org.ukindex.html. Channel 4 Schools is at http:www.schools.channel4.co.uk c4schools; CNN is at http:www.cnn. com