DVD movies look just fine on TV. But if you've recently bought a high-definition screen, you may be surprised to discover that current DVD movies don't actually play in high definition. The spectacular resolution of your screen is being wasted.

So Sony came up with a DVD format called Blu-Ray. Buy a Blu-Ray player and movies in the Blu-Ray format, and you'll be in high-def heaven.

But Toshiba and NEC also devised a high-definition DVD format, called HD-DVD. And the two formats are incompatible.

Sony persuaded many electronics giants and movie studios to endorse Blu-Ray: Apple, Panasonic and 20th Century Fox among them. But the HD-DVD faction has arrayed an army of its own, including Microsoft, Sanyo and Warner Brothers.

Analysts are predicting that the impending format war will make the VHS-Betamax war of the mid-1970s look like a warm-up act. The obvious solution would be for the two camps to get together and compromise.

Each format has some advantages — Blu-Ray discs hold more video, for example, but HD-DVD discs are cheaper to produce. (Both types of players will be able to play conventional DVDs.) These minor differences aren't insurmountable, but with so much money at stake, after more than a year of negotiations, neither side will budge.

The obvious losers are movie fans. They risk buying a $1,000 player that can play only half of available movies. Worse, when one format finally wins, some customers would have bet on the wrong horse.

That's such a frightening scenario that movie fans may not buy anything at all in 2006. They'll hunker down with their current DVDs, or switch to increasingly popular alternatives like on-demand cable programming, until the war is over.

In that case, 2006 might not just be remembered for its DVD format war. It will also be the year that the high-definition DVD arrived — and landed with a thud. — David Pogue