Blu-ray Disc is a high-density optical disc format similar to DVD. Blu-ray is the type of disc used for PlayStation 3 games and for playing high-definition (HD) movies. In the past, there were other standards for such movies, such as the HD DVD format. Blu-ray won what is called the format war.
A dual-layer Blu-ray disc can store up to 50GB (gigabytes) of data. This is over five times the capacity of a DVD, and over 70 times more than a CD or VCD.
The disc was developed by the Blu-ray Disc Association (BDA). a group of consumer electronics, personal computer and media manufacturers. The format was developed to enable recording, rewriting and playback of high-definition video (HD), as well as storing large amounts of data.
While current optical disc technologies such as DVD, DVD±R, DVD±RW, and DVD-RAM rely on a red laser to read and write data, the new format uses a blue-violet laser instead. This is where the name is from.

License information: CC BY-SA 3.0 and GFDL
MPAA: G
Go to source: https://simple.wikipedia.org/wiki/Blu-ray_Disc