CDRW (Rewritable)

CDRW media allows upto 80 minutes or 700MB of data to be recorded to each disc. CDRW media is used typically to back up smaller files such as document and imagery and can also be used to burn audio file for use in stand alone devices.

The difference between CDR and CDRW is that you can rewrite CDRW. They can be used many times, standard CDR media can only be written to once then the data can never be changed or altered.