These days, the term blank media usually refers to recordable CDs and DVDs, although it describes older formats like floppy disks as well. Recordable CDs and DVDs can be used to back up and archive files from a computer, or to play music in a CD player or movies on a DVD player.
Recordable CDs usually come in the CD-R or CD-RW formats. The former can be recorded to just once, and the latter can be recorded to over and over (the RW stands for "re-writable"). Most modern CD players will play music that was recorded on a CD-R or CD-RW.
Recordable DVDs come in the same formats, DVD-R and DVD-RW. Just like CD blank media, DVD media will play in most modern DVD players (although the DVD-R format is more reliable for DVD playback than DVD-RW). Both can be used to effectively store large amounts of data. Learn more about blank media below.
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