Don't let the fact that Toy Story is "the first full-length computer- generated cartoon" put you off this film. It's great cinema. Toy Story works for one simple reason - the clever technology plays second fiddle to the plot. It makes a lot of sense to make a film about toys that came alive on a computer. True, it could have been done as a conventional animation, but the feel would not have been right.

Toy Story shows the way technology is heading. In some of the street scenes, the images are so realistic you have to look hard to convince yourself that these are not real cars going down real streets. But Disney insists that every frame in the film is computer generated.

Hollywood already uses computer systems to enhance scenes and remove blemishes, but perhaps some day conventional filming, with a lead actor in the middle of a big scene, will disappear completely.

Four or five years ago, directors began looking at separating the main action from the background. Shooting on major pictures sometimes takes place with the main actors in front of a blue screen; they are added electronically into the action later. It is possible to shoot the actors in the set and put in the extras afterwards. With the release of Toy Story, it now seems inevitable that some exteriors, for car chases for example, will soon be computer generated.

The only place where the "reality" of Toy Story breaks down is when a human appears on the screen. They look completely false.

But before would-be Arnold Schwarzeneggers start to relax and feel safe, they should realise that several computer programmers have come up with far superior computer simulations, and it cannot be long before a computer actor can be used in some of the simpler scenes. In the future, we may even see a movie with real backgrounds and computer-generated actors. They might be a little wooden, but then some of Hollywood's biggest names are rather wooden compared to wonderful Buzz Lightyear and the inappropriately named Woody.

`Toy Story' is on general release from 22 March.