Any type of CD or DVD drive is referred to as an optical drive. There are many different options for optical drives. The simplest option is the standard CD-ROM drive. This drive gives the laptop the ability to read data from a CD. A CD-RW drive gives the laptop the ability to read and write to CDs. In order to write to a CD, a blank CD will need to be provided. CD-RW drives, or CD burners also have the ability to re-write to a CD. A CD can hold up to 700 MB of data, or the equivalent of 486 floppy disks.

A DVD drive gives the laptop the ability to read data from a DVD. This drive will allow users to watch movies on their laptops, among other abilities. A DVD-+RW drive gives the laptop the ability to read and write to a DVD. There are two different stands to write to a DVD: DVD+RW and DVD-RW. Most drives are dual standard compatible, meaning it has the ability to write in either format. A DVD can hold up to 4.37 GB of data, single layer, or 8.74 GB of data, dual layered. A 4.37 GB DVD holds the equivalent of 3107 floppy disks.

The speeds that a CD-RW drive runs at is represented by something similar to the following scheme: 12x8x48. The first number, 12, corresponds to the speed the drive can write to a CD. A 12x drive can write at 7.8 MB per second. The second number, 8, corresponds to the re-write speed the drive can write to a non-blank CD. This number is typically half of the write speed. The last number corresponds to the speed that the drive can read data from a CD.

The speed that a DVD-+RW drive runs at is represented by something similar to the following scheme: 8x4x16. The first number, 8, corresponds to the speed the drive can write to a DVD. An 8x drive can write at approximately 10.5 MB per second. The second number, 8, corresponds to the re-write speed the drive can write to a non-blank DVD. This number is typically half of the write speed. The last number corresponds to the speed that the drive can read data from a DVD.
(information from http://www.osta.org)