EMZETT.Blu-ray Disc
In short: Optical disc for high-definition films and large amounts of data: 25 GB per layer, 50 GB with two layers. The name comes from the blue-violet laser.
In more detail: Blu-ray (on the market in 2006) reads with a laser of 405 nm. The short wavelength allows even finer pits than the DVD. It won the format war against HD DVD.
In Depth
Variants
BD-ROM is the pressed film and game disc; BD-R and BD-RE are writable. Ultra HD Blu-ray supports 4K resolution and HDR and holds up to 100 GB. Players can usually read older formats such as DVD and CD, too.
Games and films
The PlayStation 3 was one of the first Blu-ray players; current consoles from Sony and Microsoft read Blu-ray games. Blu-rays also have region codes (A, B, C).
Durability
The data layer lies very close to the surface, so the discs have a hard protective coating. Still: handle only by the edge, do not store without a case, protect from heat.
See also: DVD, Optical drives