Recordable and writable optical discs




There are numerous formats of optical direct to disk recording devices on the market, all of which are based on using a laser to change the reflectivity of the digital recording medium in order to duplicate the effects of the pits and lands created when a commercial optical disc is pressed. Formats such as CD-R and DVD-R are "Write once read many" or write-once, while CD-RW and DVD-RW are rewritable, more like a magnetic recording hard disk drive (HDD). Media technologies vary, M-DISC uses a different recording technique & media versus DVD-R and BD-R.

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