Short for CD–ReWritable disk, a type of CD disk that enables you to write onto it in multiple sessions. One of the problems with CD-R disks is that you can only write to them once. With CD-RW drives and disks, you can treat the optical disk just like a floppy or hard disk, writing data onto it multiple times.
The first CD-RW drives became available in mid-1997. They can read CD-ROMs and can write onto today’s CD-R disks, but they cannot write on normal CD-ROMs. This means that disks created with a CD-RW drive can only be read by a CD-RW drive. However, a new standard called MultiRead, developed jointly by Philips Electronics and Hewlett-Packard, will enable CD-ROM players to read disks create by CD-RW drives.
Many experts believe that CD-RW disks will be a popular storage medium until DVDdevices become widely available.
Also see Understanding CD Burner Speeds in the Did You Know . . . ? section of Webopedia.