- Blu-ray is a high-density optical disc format that can store high-definition video and large amounts of data using a blue-violet laser. It has a capacity of 25GB for single-layer discs and 50GB for dual-layer discs. - Blu-ray was developed to enable recording, rewriting, and playback of high-definition video. It uses a shorter wavelength blue-violet laser which allows for greater data density and storage capacity than DVDs. - Major movie studios and consumer electronics manufacturers have adopted Blu-ray as the standard for high-definition optical discs, giving it an advantage over the competing HD DVD format.