Chapter 32. Using CDs and DVDs

CDs (compact disk) and DVDs (digital versatile disk) are media for storing information. In that regard, they're like any other type of storage media, such as hard disks. But unlike those other types of disks, CDs and DVDs are optical media, not magnetic media. That means they use a laser rather than a magnet to read and write data to and from the disk.

When you copy information to a CD or DVD, the laser essentially burns the data to the disk. That's why copying files to CDs is commonly referred to as burning to the disk.

This chapter focuses on the tools included in Windows 7 that you can use to use and create CDs and DVDs. First, let's take a quick look at the different types of optical media.

Understanding CDs and DVDs

Even though CDs and DVDs look exactly alike, there's a big difference in capacity. A CD holds about 650–700 MB of data. A DVD holds about 4.7 GB (or about 4,700 MB). In other words, one DVD can hold more information than six CDs. This is also why albums are sold on CDs and movies on DVDs — there isn't enough room on a CD to store a feature-length movie.

The newest media type, Blu-ray, has the same physical dimensions as CDs and standard DVDs, but uses a blue-violet laser that has a shorter wavelength than the red laser used on older formats. This shorter wavelength makes it possible for Blu-ray media to hold up to 50 GB (using dual-layer media). Because of its higher ...

Get Windows® 7 Bible now with the O’Reilly learning platform.

O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.