|(storage)||Digital Versatile Disc - (DVD, formerly "Digital Video Disc") An optical
storage medium with improved capacity and bandwidth compared
with the Compact Disc. DVD, like CD, was initally marketed
for entertainment and later for computer users.
A DVD can hold a full-length film with up to 133 minutes of
high quality video, in MPEG-2 format, and audio.|
The first DVD drives for computers were read-only drives ("DVD-ROM"). These provide over seven times the storage capacity of CD-ROM (4.7 GBytes). DVD-ROM drives read existing CD-ROMs and music CDs and are compatible with installed sound and video boards. Additionally, the DVD-ROM drive can read DVD films using an advanced (MPEG-2) video board, required to decode the high resolution video format.
The first drives, using a single-layer disc of 4.7GB, were expected to be available during the second half of 1996 from Toshiba, Philips, Sony, Hitachi and others. In 1997, dual-layer discs were expected to increase the disc capacity to 8.5 GB. Double-sided, dual-layer discs will eventually increase the capacity to 17 GB.
Write-once DVD-R ("recordable") drives record a 3.9GB DVD-R disc that can be read on a DVD-ROM drive. The first DVD-R drive was expected by mid 1997.
By the end of 1997, the rewritable DVD-RAM (by false analogy with random access memory) drive was expected to become available. DVD-RAM drives read and write to a 2.6 GB DVD-RAM disc, read and write-once to a 3.9GB DVD-R disc, and read a 4.7 GB or 8.5 GB DVD-ROM. Also, it was expected that a DVD-RAM disc would be readable on both the DVD-R and DVD-ROM drives.
Background. RCA home. http://www.zdnet.com/products/special/current/dvd.html. http://www.zdnet.com/products/special/current/dvdsum.html.