DVD-ROM

A new type of read-only compact disc that can hold a minimum of 4.7GB (gigabytes), enough for a full-length movie. Many experts believe that DVD-ROMs will eventually replace CD-ROMs, as well as VHS video cassettes and laser discs. Currently, however, DVD-ROMs are more promise than reality. There are only a few DVD-ROM devices currently on the market and even fewer DVD-ROM titles.The DVD-ROM specification supports disks with capacities of from 4.7GB to 17GB and access rates of 600 KBps to 1.3 MBps. One of the best features of DVD-ROM drives is that they are backward-compatible with CD-ROMs. This means that DVD-ROM players can play old CD-ROMs, CD-I disks, and video CDs, as well as new DVD-ROMs. Newer DVD players can also read CD-R disks.DVD-ROMs use MPEG-2 to compress video data.