First there was VHS vs. Betamax, then Netscape vs. Internet Explorer. Now itís Blu-ray vs. HD-DVD, two formats battling for dominance to bring high-definition DVD movies to your television. One format is winning.

First there was VHS vs. Betamax, then Netscape vs. Internet Explorer. Now itís Blu-ray vs. HD-DVD, two formats battling for dominance to bring high-definition DVD movies to your television. One format is winning.

Dan Ackerman, senior editor at the technology Web site Cnet, answered some questions for us.

Question: Whatís the difference between HD and Blu-ray?
A.: To the average consumer, there really isnít a lot of difference between the formats. They both look fantastic. Theyíre both high-definition.
Q.: What companies created them?
A.: HD-DVD is principally supported by Toshiba. Blu-ray was developed by Sony.
Q.: Why canít we have two formats?
A.: We certainly can have two formats. We had VHS, and we had Beta for a while. But eventually one of those won out.
Q.: Does Blu-ray appear to be winning?
A.: The format war ended when Warner Bros. announced support last week for Blu-ray exclusively, and they are the biggest movie studio, with the most releases. Having all those movies coming out exclusively on Blu-ray really means the fight is over. It means that HD-DVD has effectively lost.
Q.: The consumer is going to go to the format with the most movies?
A.: Exactly. These two sides have been fighting since these two formats launched to sign up movie studios to exclusive deals. Itís been kind of tit for tat and fairly equal until now. The Warner Bros. decision was the 10-megaton bomb.
Q.: What should I do if I have an HD-DVD player?
A.: There will still be movies in the HD format, and there will be Warner Bros. movies in the format until April. And it will still play your old DVDs.
Q.: So itís not that bad?
A.: But ... the momentum is going to shift to Blu-ray very heavily.