Blu Ray is the next generation DVD format that was developed to enable recording, rewriting and playback of high definition video (HD), as well as storing large amounts of data. The format has 5 times the storage capacity of traditional DVDs and can hold up to 25GB on a single-layer disc and 50GB on a dual-layer disc.
Blue Ray uses a blue-violet laser instead of the traditional red laser and is backwards compatible with DVDs and CDs. You will need to have a Blu Ray drive in order to take advantage of the new media. These devices will be expensive during the initial release until more manufactures start making the drives and the new format becomes more widely used. It is thought that Blu Ray will eventually replace DVDs.
One of the biggest advantages of Blu Ray is ability to offer movies in High Definition (HD). High Definition can provide up to 5 times the definition of traditional DVDs thanks to its extra storage capabilities.
Blu Ray is competing with HD-DVD, which uses a similar blue-violet laser and high storage capacity. Blu Ray is able to fit more data on the same size disc since the laser spot can be focused with greater precision.
There are plans to offer Blu Ray drives for computers as well and it will eventually replace the DVD drives currently in use.