Presenting information and knowledge about cdr!
So simple yet uncertain. Those who read will find out.
CDR Common data rate
Another definition of cdr:
Currently most CDROM and CDi discs and players are read only devices so unlike video tapes they cannot be used to record video music or other data. CDROM recorders priced at around £500 look likely to be on sale within two years. Blank discs will cost about £15.