Answer: -R
A designation of ___ means that a blank optical disc can be recorded to only once.
The encoding material sits atop a thicker substrate (usually polycarbonate) that makes up the bulk of the disc and forms a dust defocusing layer. The encoding pattern follows a continuous spiral path covering the entire disc surface and extending from the innermost track to the outermost track. The data are stored on the disc with a laser or stamping machine and can be accessed when the data path is illuminated with a laser diode in an optical disc drivethat spins the disc at speeds of about 200 to …
CD-R (COMPACT DISC – Recordable) is a digital optical disc storage format. A CD-R disc is a compact disc that can be written once and read arbitrarily many times. CD-R discs (CD-Rs) are readable by most plain CD readers i.e. CD readers manufactured prior to the introduction of CD-R.
Optical disc drive - Wikipedia
Optical disc - Wikipedia
Optical disc - Wikipedia
CD-R - Wikipedia
Some drives can only read from certain discs but recent drives can both read and record also called burners or writers (since they physically burn the organic dye on write- once CD-R DVD-R and BD-R LTH discs ). Compact disc...

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