Today, the DVD player is the newest way of watching a movie, which has great quality, all in a disk form. A DVD is similar to a CD but it has a much greater capacity. A standard single layer DVD holds about seven times more data than a CD. Because of this, a DVD can hold a full-length movie including many special features that you don't get at a movie theater. A DVD player usually includes the following features.

· Up to 133 minutes of high quality video
· A soundtrack presented in up to 8 languages
· Subtitles in up to 32 languages
· Viewing options such as letterbox, panoramic, or pan-and scan

DVD's can store more information than CD's for a few important reasons.

·Higher-density data storage: This simply means that there are more pits and tracks, which are the things that are too small to see that, are lasered onto the disk and are read by the DVD player
· Better Error correction: A DVD player has more room for information so it has a better and more efficient error correction scheme so that they don't skip and they run very smoothly
· Multilayer Storage: A DVD can have up to four layers, two on each side instead of one like a CD. Each layer increases the length of the DVD but does not double it. The laser can read the first layer and then look through that to the second layer.

Data storage on a DVD

DVD's and CD's are both the same diameter and thickness and they are both made of mostly the same materials. Since many DVD's have multiple layers, there has to be a way to read through the first to the second layer. The first layer is coated with a semi-transparent layer of gold. The second layer is an opaque aluminum mirror like a CD uses. The layer can focus on the gold layer or it can shine through to focus on the opaque layer.

That is how the newest movie watching technology works.

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