CD-RW

Compact Disc ReWritable (CD-RW) is a type of CD disc and drive that enables you to write onto a disc in multiple sessions. One of the problems with CD-R discs is that you can only write to them once. With CD-RW drives and discs, you can treat the optical disc just like a floppy or hard disk, writing data onto it multiple times.
The first CD-RW drives became available in mid-1997. They could read CD-ROMs, and could write onto today's CD-R discs, but they could not write on normal CD-ROMs. This means that discs created with a CD-RW drive can only be read by a CD-RW drive, since it uses a different form of recording to the one a normal CD-ROM drive is capable of reading. 
However, a new standard called MultiRead, developed jointly by Philips Electronics and Hewlett Packard, enables CD-ROM players to read disks create by CD-RW drives.
CD-RW, even with the advent of DVD-RW and DVD+RW Discs, CD-RW still remains hugely popular as a way of testing Operating Systems on Real Hardware, without using lots of CD-R's.
== References ==
* Bennett, Hugh. "CD-E: Call it Erasable, Call it Rewritable, but will it Fly?" CD-ROM Professional Sept. 1996: 28+
== External links ==
* Understanding CD-R & CD-RW by Hugh Bennett