Science: In the fast lane on the sofa: Susan Watts previews the social revolution that is now speeding towards us along 'information superhighways'

Senator Al Gore, father of the US Vice-President, helped transform the face of American society. Forty years ago, he lent his political muscle to the Federal Aid Highway Act (1956) that provided dollars 31.5bn for the concrete and asphalt interstate highway system and thus cemented the American love affair with the automobile - an obsession that has shaped the physical geography of American cities, and the lives of its people. From shopping malls to drive-in movies, the social effects of the automobile are all pervasive.

Now the Senator's son also has a vision of superhighways that will link businesses, homes, universities, broadcasters and government. Vice-President Al Gore's thoroughfares, however, will carry streams of digital information instead of cars and lorries. But the advent of these 'information superhighways' promises no less a social revolution than the freeways that filled his father's dreams. And there will be movies, too.

Mr Gore's vision is based on the computer or television screen in the living room becoming an electronic fount of knowledge. It will allow people to shop from their sofas - ordering anything from food and theatre tickets to new cars, holidays and homes. Virginia Bottomley would no longer need to ask Marks & Spencer to open early - she could browse through a virtual version of an empty store stocked with the latest lines and even try out a new dress on a digitised version of herself on screen.

An information superhighway requires not only the technology to carry the information. The information being carried must also be in digital form, so that it can be processed. After all, there would be no point in building high-speed motorways if everyone were driving Model-T Fords.

Computing, telecommunications and entertainment companies are now uniting to produce, at least in trial form, digital television broadcasts and digital video. The latter will be sent over ordinary telephone lines.

The technological jigsaw pieces from which the superhighways will be built are also slotting into place. In Britain, BT's telephone network is now entirely digitised - carrying its information along fibre-optic cables at the speed of light. The cable industry believes it will wire up 51 per cent of homes over the next five years. But perhaps the most important driving force has been the advent of networking technologies that can squeeze digital information through even old-fashioned copper telephone wires and, most importantly, do so at a price people can afford.

At the front end of the information networks is technology that will sit in the consumer's living room. IBM, among others, has said it intends to cram all the processing power of its latest personal computers into a television-top box that will decipher the plethora of signals that reach the home. Philips and Bell Atlantic are developing intelligent terminals, a cross between a television and a computer, that will flash up 'menus' on the screen for users to choose the service they want as simply as operating a video recorder - using play, stop and pause buttons and perhaps even voice control.

So the lines are in, or being installed, and the computer or television screens that will deliver the information to our eyes and ears are on their way. What has been missing is an electronic warehouse big enough to store and control the data that will travel down the fibre-optic highways.

This is where the 'Media Server' recently announced by Oracle, a dollars 1.5bn US software supplier, comes in. This may sound like an electronic version of a political spin-doctor, but in fact the company has created a giant modem capable of handling huge amounts of data at a phenomenal rate and virtually free of errors.

The first service to be made available on the Media Server in Britain will be 'video-on-demand'. This lets people order videos that have been digitised and stored on the Media Server's databanks. BT will test the system using its own employees at research laboratories near Ipswich in the spring, expanding the service to 2,500 homes in East Anglia in the autumn. The viewer will be able to choose a film, order it via the screen in their home, and the Media Server will then deliver a copy, in digital code, over the telephone lines for the intelligent box linked to their television to convert back into comprehensible moving images.

Dave Thunder, a director in the telecommunications services division of the Gartner Group, says the Oracle software opens up a vast range of possibilities: 'Nobody thought, even a year ago, that people would be able to do this with ordinary copper telephone lines.'

Superhighways will put hundreds of video and film services under the control of the individual, bringing fresh meaning to the concept of 'information overload'.

Users would also be able to create their own evening news service by programming their interests into a computer that scours the airways for relevant items. Or they could create their own personal television channel from the hundreds available, with programmes and timing to suit their lifestyle. This concept, known as 'echo television', is not far away. Capital Cities/ABC, one of the world's largest communications companies, with television, radio and newspaper interests, has already teamed up with Oracle and plans to create personal news services within the next few years.

But the effect of the technology will be felt far beyond the living room. Employers will need only half the office space as people telecommute for at least half of their working lives - liaising with the office from terminals in their homes.

As this spreads to a cluster of companies operating in the same town, there will be knock-on effects for local government and construction - changes rippling outwards into the economy as a whole. Computing companies in Britain are trying to persuade government departments to become involved. Plans are under way to create Europe's first digital superhighway by persuading the DHSS to buy a system that would allow it to send information on benefit entitlements to regional databases, updated by network-wide broadcasts.

One major weakness in all this is the underlying assumption that people will want to use such services. Oracle points to take-up of other similar services to support its optimism. These include the rapid growth of telephone-based schemes dealing in car insurance and banking services. At first consumers were suspicious about the reliability and security of telephone transactions, but their fears diminished with familiarity.

Superhighways will raise their own personal privacy concerns. As people use their screens, the computer behind them could effortlessly create personal profiles of interest to advertising companies. Those who weary of today's junk mail might fear the possibility of endless finely tuned 'junk information'.