Sony has taken another step towards making video tape recorders obsolete by unveiling its new digital video disc player.

The new machines look like video recorders but play discs instead of video tapes. Electronics companies say the DVD players are the greatest leap forward in consumer technology since the launch of the compact disc in 1982.

Digital video discs look like CDs but can store massive amounts of data. Initially the discs will store 4.7GB of data - more than enough for a two-hour movie with extra multimedia features and seven times the amount that can be stored on an ordinary CD.

Like CDs, DVDs also will allow people to skip through scenes at the press of a button.

But to reap the technology's full benefit, users must have a wide-screen television. And the technology doesn't come cheap. The players cost about �500 and the few discs now available sell for about �20.

The new DVD players also cannot record. That is why, according to Barry Fox of New Scientist magazine, now may not be the time to buy.

"If you're not a movie buff who's crazy about hi-fi surround sound, you're paying �500 for a player to play movies. In effect you're getting a recorder that can't even record."

Nevertheless Mr Fox says DVD technology is one to watch.

It'll be several years before people start replacing their video recorders with DVD but with all the advantages that the technology brings, there seems no question that this is the technology of the future.