These are two similar, but competing technologies for the higher capactity recordable storage medias that are currently becoming popular and will eventually supercede exisiting DVD media. HD-DVD and Blue-Ray have a much higher storage potential than DVD, up to 10 times its capactity.
Blu-Ray is supported by the Sony Corporation and is the media of choice for the PS3 HD-DVD is currently being adopted by Microsoft for use in their XBox 360 console.
Similar to a DVD or compact disc, the blu-ray Disc(BD) is capable of storing up to 25GB on Single layer and 50Gb on dual layer as opposed to 4/8GB for DVD and 700Mb for a CD.
Because the laser used to read the data from the disc is blue-violet in colour.
Around 23 hours of Standard definition(SD) video on a dual layer 50GB disc or 9 hours of High definition(HD) video.
MPEG2 and MPEG4, with SMPTE VC-1 which is based on Microsoft WMV format.
The new Playstation 3 (PS3) from Sony will utilise the Blu-ray format. This will mean much greater storage capacity for games.
High Definition DVD.
A digitial optical media simliar in size to a DVD or CD. Each HD-DVD disc can contain 15GB in a single layer or 30GB in a dual layer. A blue laser is used, similar to that used in the blu-ray format.
Around 23 hours of Standard definition(SD) video on a dual layer 50GB disc or 9 hours of High definition(HD) video.
The new Xbox 360 from Microsoft now has an external HD-DVD disc module so that it can compete effectively with the Sony PS3 Blu-ray based console.