The compact disc (CD) is a digital optical disc data storage format that was co-developed by Philips and Sony to store and play digital audio recordings. In August 1982, the first compact disc was manufactured. It was then released in October 1982 and branded as Digital Audio Compact Disc.

Standard CDs have a diameter of 120 millimeters (4.7 in) and are designed to hold up to 74 minutes of uncompressed stereo digital audio or about 650 MiB of data. Capacity is routinely extended to 80 minutes and 700 MiB by arranging data more closely on the same sized disc. The Mini CD has various diameters ranging from 60 to 80 millimeters (2.4 to 3.1 in); they are sometimes used for CD singles, storing up to 24 minutes of audio, or delivering device drivers.

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