ABSTRACT
The ultimate expression of the original video disc is the digital video disc (DVD). The DVD now crams a full movie or an equivalent amount of video data onto a 5-inch CD-size disc. A photograph exists of a Toshiba DVD player, but your author spent considerable time at a Fortune 500 communications giant photographing blocks of wood with a two-way radio shell wrapped around it. The DVD is a multipurpose technology suited to both entertainment and computer uses. As an entertainment product, the DVD is designed to be used for full-length movies with up to 133 minutes of high-quality video and audio. At the same time DVD can be used with computers as an alternative to CD-ROM, providing as much as 17 gigabytes of storage capacity in its dual-side/dual-layer configurations. The dual layering, which allows doubling of the disc's capacity, is achieved by adding a second layer of pits and lands beneath a semire-flective coating.
