Digital video disc (DVD)
From The Glossary of Digital Photography
Also called digital virtual disc. An optical disc that can store information such as images; its more common use is to store and distribute movies. The DVD is the same size as a CD but holds much more information. New technologies are developing such that a double-layer DVD can hold up to about 8.5 GB of information; a double-layer, double-sided DVD can hold up to 17.1 GB of information. With digital image sizes growing, the DVD has become a common storage method for images and is used frequently in digital photography. There are two competing formats called DVD+ (DVD plus) and DVD- (DVD minus). DVD+ is also known as DVD+R and DVD- is also known as DVD-R. DVD+ was developed by DVD+RW Alliance and is not supported by the DVD Forum as an 'official' DVD format. DVD- is a DVD format supported by the DVD Forum. Most modern DVD players and recorders can deal with DVD- discs The most popular DVD readers are hybrid readers, which can read both a DVD- and a DVD+, since neither format has become the single standard format. Very few single-format readers are available. See also disc; disk
