Hitting stores' shelves late next year will be two different kinds of high-definition DVD players. Each supports a different format; one is called Blu-Ray, the other dubbed HD-DVD, and their image quality is equivalent. Those encoded in the Blu-Ray format won't be compatible with HD-DVD machines and vice versa.

It's impossible to say which format will be the dominate one. Blue-Ray discs have more storage capacity--50 gigabytes, or enough for a high-definition feature film and plenty of extras. But, to manufacture them will involve the costly proposition of building the infrastructure from the ground up, with all new facilities and equipment.

HD-DVDs' 25 gigabytes of storage can also hold an HD feature film, but that's about it. They can, however, be made in the same plants that are now being used to make standard definition discs--a much cheaper alternative. "That means that they'll be cheaper for consumers, which will give HD-DVD the chance to get a lot of volume in the market more quickly," says GartnerG2 analyst Paul O'Donovan.

Companies that support HD-DVD are:

Toshiba, Paramount Pictures, Universal Studios, Time Warner studios, Warner Bros. and New Line Cinema.

Companies that support Blue-ray format are:

The Walt Disney, Sony, Hitachi, Panasonic, Pioneer, Phillips Electronics and Samsung.

As of now, whether HD-DVD or Blue-Ray will win out the other format is any body's guess. But HD discs will hit the store shelves by holidays 2005