Blu-ray Disc

Blu-ray Disc (BD) is an optical storage disc media format. Its main uses are high definition media & data storage. The disc has the same dimensions as a standard DVD or CD.
The name Blu-ray Disc is derived from the BLUE LASER (violet coloured) used to read and write this type of disc. Because of its shorter wavelength (405 nm), substantially more data can be stored on a Blu-ray Disc than on the DVD format, which uses a red (650 nm) laser. A dual layer Blu-ray Disc can store 50 GB, almost six times the capacity of a dual layer DVD.
Blu-ray Disc was developed by the Blu-ray disc association, a group of companies representing consumer electronics, computer hardware, and motion picture production. The standard is covered by several patents belonging to different companies. As of April 2008, a joint licensing agreement for all the relevant patents had not yet been finalized.

Blu-ray Disc titles have been released in the United States, and more than 250 in JAPAN.
During the high defination optical disc format war, Blu-ray Disc competed with the HD DVD format. On 19th Feb 2008, Toshiba—the main company supporting HD DVD — announced it would no longer develop, manufacture and market HD DVD players and recorders, leading almost all other HD DVD supporters to follow suit, effectively naming Blu-ray the winner of the format war.