BDROMs

BD-ROM stands for Blu-ray Disc Read-Only Memory. It is a type of Blu-ray disc that contains pre-pressed data and is intended to be read by a Blu-ray player or drive but not written or erased by the user. BD-ROMs are commonly used for commercially released movies, television programs, software, and other forms of data distribution.

BD-ROM discs use a blue-violet laser and a high-density data structure to store information. The standard capacity is 25 gigabytes per single layer and 50 gigabytes for a dual-layer disc, with some formats allowing up to 100 gigabytes on a triple-layer disc. In practice, the majority of films and titles on BD-ROM are produced on 25 or 50 GB discs, while higher-capacity media are rare and mainly used for special applications.

Content on BD-ROMs is encoded with modern codecs such as MPEG-2, MPEG-4 AVC (H.264), or VC-1, and may include interactive features via BD-Java (BD-J). Copy protection and region controls are commonly employed, including AACS encryption and region codes to restrict playback to certain geographic areas. Some discs also offer network-connected features via BD-Live.

BD-ROM is one of the core Blu-ray formats defined by the Blu-ray Disc Association. It coexists with writable Blu-ray formats (BD-R, BD-RE, including the higher-capacity BD-R/RE XL) and is designed for reliable, mass-produced content distribution. Blu-ray players certified for BD-ROM playback can read these discs alongside other Blu-ray formats.