Blu-ray Dics

In 1997 DVD revolutionized the movie industry and within couple of years almost completely replaced VHS system. But the technology is moving very fast and now DVD is facing a big challenge from blu-ray technology. Blu-ray introduced high defination audio and video and its storage capicity is much more than the DVD.A single-sided, standard DVD can hold 4.7 GB (gigabytes) of data which is enough to incoporate a standard length movie. But a high-definition movie, which has a much clearer image takes up about five times more bandwidth and therefore requires a disc with about five times more storage. To watch a blu ray movie you need a relevant technology.
At present DVD is still in more demand than the blu ray but this a just start and when blu ray technology becomes more common and competitive then prices are expected to fall and thats the moment when blu ray system will start replacing dvd.
In general blu ray simply means a high defination audio and video formate and of course better quality.