Data capacity of DVDs used so far is not adequate to enable high definition recording (8.5 DVD-9 and 9.4 GB DVD-10 disc)

Sony has developed a Blu-ray disc technology for recording high definition Full HD (1920 x 1080 pixels) movies that enable to save („press“) 25 GB of data on one–layer BD disc and 50 GB on a two-layer disc (respectively BD 46,612 GB).

The dimensions of a Blu-ray disc (BD) are the same as those of an ordinary CD/DVD disc. Higher data capacity is achieved by using a blue (technically blue-violet) laser for data reading. Out of this also the name - Blu-ray.