Transcription: A compact disc or CD is a plastic disc containing a thin metallic layer that's used for storing large amounts of information. The most popular use for CDs today is for recording and playing back high quality sound. A high precision laser beam is used to burn microscopic pits in the thin metal layer of a master disc. The pits are laid down in patterns that can be read by a compact disc player. Thousands of CDs can be made from a single master disc. A CD player contains a low-power laser and high-precision lenses and mirrors. A servo motor positions the optical elements to a track on the disc. T ...
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