Blu-ray
The Blu-ray Disc, often known simply as Blu-ray, is a digital optical disc storage format. It is designed to supersede the DVD format, capable of storing several hours of video in high-definition video. The main application of Blu-ray is as a medium for video material such as feature films and for the physical distribution of video games for the PlayStation 3, PlayStation 4, PlayStation 5, Wii U, Xbox One, and Xbox Series X. The name "Blu-ray" refers to the blue laser used to read the disc, which allows information to be stored at a greater density than is possible with the longer-wavelength red laser used for DVDs. The plastic disc is 120 millimetres in diameter and 1.2 millimetres thick, the same size as DVDs and CDs. Conventional or pre-BD-XL Blu-ray Discs contain 25 GB per layer, with dual-layer discs being the industry standard for feature-length video discs. Triple-layer discs and quadruple-layer discs are available for BD-XL re-writer drives.