CD and DVD Formats Explained

With so many kinds of blank CDs and DVDs available, it can be difficult to know which is best for your needs. This guide is a quick reference to the major formats.

CD Formats

CD-R: CD-R discs can be formatted once -- the "R" stands for recordable. This means that once data is recorded onto the disc (or "burned," as techies like to say), it cannot be re-recorded, erased, or altered. CD-R discs, which are available in capacities of 650MB and 700MB, are good for burning music, backing up data, or transferring files between computers. Their use is limited by their inability to record more than once, however -- don't buy CD-Rs if you want to save successive versions of a document onto the same disc.

CD-RW: CD-RW discs can be recorded multiple times -- the "RW" stands for rewritable. Unlike CD-R discs, which can only be burned once, the data on a CD-RW disc can be erased, altered, or re-written hundreds of times. This lets CD-RWs act just like floppy discs, as the information stored on them can be updated as many times as necessary. It is important to note that not all car and home stereos are compatible with CD-RW format -- if you intend to burn music onto CD-RWs, check that your player is compatible first.

DVD Formats

DVD-R: DVD-R discs can be recorded on once -- as with CD-Rs, the "R" stands for recordable. DVD discs look just like CDs, but hold substantially more data -- 4.7GB or more. DVD-Rs cannot be rewritten or erased, so they are best suited for data backup, burning videos, or transferring large amounts of data that could not fit on a CD.  DVD-R discs can be played in the vast majority of DVD players and drives.

DVD-RW: DVD-RW discs can be recorded multiple times -- as with CD-RWs, the "RW" stands for rewritable. Like CD-RWs and floppy discs, DVD-RWs are great for users who will need to alter or erase the data they have burned onto disc, as these discs can be rewritten up to 1000 times. Many DVD players can play DVD-RW discs.

DVD+R: Like DVD-R discs, DVD+RW discs can be recorded once. While their capabilities are the same as DVD-R discs, DVD+R media use a different technology and are supported by a different set of manufacturers than the DVD-R format. DVD+R drives are featured in products from Sony, Dell, Compaq, Hewlett-Packard, and other manufacturers; most of these drives are compatible with DVD-R and -RW discs as well.

DVD+RW: DVD+RW discs are the rewritable version of DVD+R discs. Like other RW discs, the data on DVD+RWs can re-recorded, altered, or erased hundreds of times. Supported by the same manufacturers as DVD+R discs, DVD+RW media is the choice of many top computer makers.