A Compact Disk (CD) is an optical disc used to store digital data. It can be ported from one place to another and is round medium made up of molded polymer. The data is recorded electronically; originally the compact disk was developed for storing digital audio. It is also used for the purpose of storing video, text, and other digital form. The compact disks replaced the phonograph record which was used to playing back music. It consists of one or more metal layers on which the data is stored. The most prevalent compact disks are used by the music industry to store digital recordings and CD-ROMs (compact disk- read only memory) are used to store computer data.
