COMPACT DISC

(CD), a molded plastic disc containing digital data that is scanned by a laser beam for the reproduction of recorded sound and other information. Since its commercial introduction in 1982, the audio CD has almost completely replaced the phonograph disc for high-fidelity recorded music. Coinvented by Philips Electronics N.V. and Sony Corporation in 1980, the compact disc has expanded beyond audio recordings into other storage-and-distribution uses, notably for computers (CD-ROM) and entertainment systems (videodisc). This article briefly describes the physical characteristics and performance of the audio compact disc. For descriptions of machine-readable discs containing multimedia or video data, see the articles CD-ROM and videodisc.