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DVD

DVD
DVD logo.svg
DVD-Video bottom-side.jpg
The backside of a Sony DADC-manufactured DVD
Media type Optical disc
Capacity 4.7 GB (single-sided, single-layer – common)
8.5 GB (single-sided, double-layer)
9.4 GB (double-sided, single-layer)
17.08 GB (double-sided, double-layer – rare)
Read mechanism 650 nm laser, 10.5 Mbit/s (1×)
Write mechanism 10.5 Mbit/s (1×)
Standard DVD Forum's DVD Books and DVD+RW Alliance specifications
Developed by Philips, Sony, Toshiba and Panasonic
Weight 16 grams (246 grains)

DVD (an abbreviation of "digital versatile disc" or "digital video disc") is a digital optical disc storage format invented and developed by Philips, Sony, Toshiba, and Panasonic in 1995. The medium can store any kind of digital data and is widely used for software and other computer files as well as video programs watched using DVD players. DVDs offer higher storage capacity than compact discs while having the same dimensions.

Pre-recorded DVDs are mass-produced using molding machines that physically stamp data onto the DVD. Such discs are a form of DVD-ROMs, because data can only be read and not written or erased. Blank recordable DVD discs (DVD-R and DVD+R) can be recorded once using a DVD recorder and then function as a DVD-ROM. Rewritable DVDs (DVD-RW, DVD+RW, and DVD-RAM) can be recorded and erased many times.

DVDs are used in DVD-Video consumer digital video format and in DVD-Audio consumer digital audio format as well as for authoring DVD discs written in a special AVCHD format to hold high definition material (often in conjunction with AVCHD format camcorders). DVDs containing other types of information may be referred to as DVD data discs.

The Oxford English Dictionary comments that, "In 1995 rival manufacturers of the product initially named digital video disc agreed that, in order to emphasize the flexibility of the format for multimedia applications, the preferred abbreviation DVD would be understood to denote digital versatile disc." The OED also states that in 1995, "The companies said the official name of the format will simply be DVD. Toshiba had been using the name ‘digital video disk’, but that was switched to ‘digital versatile disk’ after computer companies complained that it left out their applications."


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