Blu-ray

Blu-ray Disc (also known as Blu-ray or BD) is an optical disc storage medium that is predicted to be the successor to the DVD format. Its main uses are high-definition video and data storage with 50GB per disc. The disc has the same physical dimensions as standard DVDs and CDs.

The name Blu-ray Disc is derived from the blue laser (violet-colored) used to read and write to this type of disc. In part because of the shorter wavelength (405 nanometres), substantially more data can be stored on a Blu-ray Disc than on a DVD, which uses a red (650 nm) laser. A dual-layer Blu-ray Disc can store 50 gigabytes, almost six times the capacity of a dual-layer DVD, or ten and a half times that of a single-layer DVD.