A DVD is created and read just like a CD. The difference is that it can hold about 7 times more data than a CD. It does this by having bumps and tracks that are smaller than CDs. Not only that, but DVD’s can hold data in two layers, and some DVD’s are two-sided, so there are up to four layers of data on a DVD. The sampling rate and sampling precision are both higher on a DVD. The sampling rate of a DVD is 97,000 samples per second, as opposed to the 44,100 for a CD. DVDs are used for both audio and video. Super Audio CDs (SACD) were developed for audio use and use a sampling rate around 64 times that of a CD. However, because of the development of iPods and MP3 payers, most people opted for the convenience and economics of buying single songs online rather than purchasing disks and players.
DVD
How many layers of data can a DVD hold on one side?
DVD's can hold up to two layers of data on one side.
DVD
Which layer of the DVD holds the encoded date?
The polycarbonate layer.
