Blue-ray Disc commonly known as BD or Blue-Ray, falls in the category of optical disc storage media formats, and has the same dimensions as a CD or DVD, the only difference being that while a CD has a capacity of 700 MB and a DVD 4.7 GB, a Blue ray can hold around 25 GB of data!

It was created with an intention of storing larger amounts of high definition video and audio and gets its specific nomenclature from the violet-blue color of the laser that is used to read and write data to and from the disc. Blue lasers have a shorter wave length (405 nm) than a CD or DVD which uses a traditional red laser, which enables it to store more data than others.

It was actually the invention of the blue laser diodes by Shuji Nakamura, which paved the way for Blue-Rays. But it was obviously Sony, which started the application of this new medium of technology, leading to the initial DVR Blue systems that were officially revealed to the public during the CEATEC exhibition in October 2000. By February 2002, the Blue-Ray Disc Association came into existence with nine founder members. It took another year for Sony’s BDZ-S77 and BD-RE recorder to appear in the Japanese market amidst stiff competition from Toshiba’s HD-DVD sector, which enjoyed an initial advantage in the high definition video market. . It should also be noted that the initial varieties of blue-ray discs were very sensitive to scratches and had to be handled carefully, but the newer versions have a particular coating which has solved this problem to a certain extent.

Although the first Blue-Ray Disc titles were released on 20th June, 2006 using MPEG-2 video compressions, movies using (50 GB) dual layer discs came into the market only by October 2006. Sony also released their BD rewritable drive for PCs, the BWU-100A, which recorded both single and dual layer BD-R and BD-RE discs, the same year.

The  launch of  Sony’s Playstation 3, marked a high increase in sales of the Blue-ray Disc player, thereby making it overtake the HD DVDs by the mid of 2007. HD DVDs also faced an un-ceremonial exit with Warner Brothers’ announcing that after May 2008, all their movies will only be released in Blue-ray disc format. This obviously meant a switch over for their other studios like New Line Cinema, HBO etc. Major international retailers like Wal-Mart, Woolworths, etc as well as the online DVD rental site like Netflix too followed suit by dropping the HD DVDs to take to Blue-ray discs. This resulted in Toshiba deciding to terminate the production of their HD DVD appliances, thus clearing out a path for the Blue-ray disc, which has started making its mark in the various Hollywood studios like Universal Studios, Paramount Studios, etc.

Expense factor is one of the main drawbacks that Blue-ray discs face today. Moreover, as it runs on a different laser type, Blue-ray discs cannot be played in existing DVD players; but the Blue-ray drivers may accept all the current formats of CD and DVDs easily.