DVD - Digital Video Disk or Digital Versatile Disc
Digital Versatile Disc, or commonly known as Digital Video Disk is an optical disc storage media format that can be used for storing high capacity data like high quality movies and videos and even an operating system. It was developed in 1995 by 4 companies namely : Philips, Panasonic, Sony and Toshiba.
A DVD is available in many variants, including :
4.7 GB (single-sided, single-layer)
8.5–8.7 GB (single-sided, double-layer)
9.4 GB (double-sided, single-layer)
17.08 GB (double-sided, double-layer)
Physical Dimension of a DVD
A Digital Video Disk comes in 2 dimensions : 12 cm (120 mm) and 8 cm (80 mm) diameter sizes. 120 mm is the most commonly used dimension for storing Movies, Operating systems and large software. 80 mm size is suitable for small devices like a video camera.