What are HD DVD and Blu-Ray Disc?
Today’s conventional DVDs can hold 4.7GB of information, but many want a higher-capacity successor to accommodate the larger data demands of high-definition video. HD DVD and Blu-ray both use blue lasers to read and write data; because blue has a shorter wavelength than the red used in DVD and CD lasers, information can be packed more densely on a disc and a single disc can hold more. Both HD DVD and Blu-ray drives are able to read current-generation DVDs.
