DVD

DVD, short for Digital Versatile Disc (also referred to as Digital Video Disc), is an optical storage format developed in the mid-1990s by a consortium led by Philips, Sony, Panasonic, and Toshiba. It was designed to replace VHS for video distribution and CD-ROM for data, offering greater capacity and interactive features. The format supports multiple applications, including DVD-Video for movies and TV, DVD-Audio for high-fidelity sound, and DVD-ROM for data storage, as well as various recordable and rewritable variants.

DVDs come in several formats and capacities. Common uses include DVD-Video, DVD-Audio, and DVD-ROM, along with recordable options such as DVD-R, DVD-RW, DVD+R, and DVD+RW. Capacity varies by format: about 4.7 GB on a single-layer, single-sided disc (DVD-5); 8.5 GB on a dual-layer single-sided disc (DVD-9); 9.4 GB on a single-layer, double-sided disc (DVD-10); and 17.0 GB on a dual-layer, double-sided disc (DVD-18). Discs are read with a red laser (approximately 650 nm) from a polycarbonate substrate with a reflective layer, typically aluminum, protected by lacquer.

Video and audio on discs labeled DVD-Video are commonly encoded with MPEG-2 video and Dolby Digital (AC-3) or DTS audio, with PCM used in some cases. Access and distribution are frequently controlled by region codes and the Content Scramble System (CSS) copy protection. Since its introduction, DVD became a dominant home video format but has been widely supplanted by Blu-ray and streaming services, while still used for archival purposes and in regions with limited access to newer technologies.