CD-R, CD-RW, DVD, DVD+RW,
and DVD-RW

This PC alphabet soup describes the Compact Disc and Digital Versatile Disc drives found in most PCs. This article discusses the differences between these drives and how they are used in a PC.

Older PCs have CD-R drives that permit reading Compact Disc. The Compact Disc is the media that virtually all software installed into a PC is distributed upon. A single Compact Disc stores 650 to 700 Million characters (bytes) of information. In contrast a single floppy disk stores 1.44 million characters of data. Thus, a single CD is equivalent to about 480 floppy diskettes. CD-R drives are principally used to install software on a PC, but they can also be used to play music CDs.

Information is stored on CDs in different formats. A common music CD uses a CDA or Compact Disc Audio format. I recently played a CDA format CD from The Fabulous Hubcaps on my PC.

Any data file stored on a PC’s fixed disk drive can also be stored on a CD. CDA music CDs and data CDs are not mixed. However, music can be converted to an all digital MP3 format and mixed with data. A popular format for photographs is a JPG format. Any CD-R drive will read this data and with the appropriate software convert it to music played on the PC or photographs viewed on the PC.

CD-RW or Compact Disc Read Write drives can be used to burn RO (Read Only) or RW (Read Write) compact discs. The Read Only (RO) are the most popular disc to burn because they hold 700 MB and cost from $.10 to $.30 each. They backup data, MP3, and JPG files stored on a PC’s fixed disk. A single CD-RO disc can last 30 years or more. CD-RW discs can be written to and read from many times (about 100,000 times). CD-RW discs make the CD-RW drive look like a very large floppy disc. They are not used as much as CD-RO discs because they cost more, require loading extra background software, and run slower than CD-RO discs.

Digital Versatile Disc (DVD) drives usually hold movies in a special movie format incorporating copy protection. Similar to CD drives there are DVD drives that can be burned as read-only or read-write. They store 4.7 billion characters or the equivalent of seven compact discs. There are two flavors of DVD read write drives, a + and a – flavor. Some newer DVD read write drives work with both flavors, but older ones do not. DVDs are used to play movies or store and retrieve large amounts of data including MP3 and JPG files.

Can you use a CD or DVD data disc in a DVD player attached to your Television? Maybe? Maybe not? You must read the DVD player box or specifications to see the disc types it reads and what types of file formats it plays. Most all read CD and DVD discs, all play DVD movies, some play CDA discs, fewer still play MP3 discs, and some may display JPG images. As an old nerd I use DVDs because it is easier for me to get more storage than to throw out any files.