Compact disc

Compact discs (English: Compact Disc, abbreviated as CD) is an optical disc used to store data digitally. Compact discs originally developed for storing digital audio and introduced in 1982. Media remains a standard format in the playback of commercial audio recordings to mid-2006. An audio compact disc contains one or more rows stored stereo coding process 16-bit PCM at 44.1 kHz sample rate. Standard compact disc 12 cm in diameter, the smaller diameter of 8 cm. Compact disc 12 cm in diameter can accommodate approximately 80 minutes of audio data. Compact discs 8 cm in diameter, which is sometimes used for a demo CD, is able to accommodate approximately 20 minutes of audio data. Compact disc technology was later adopted for use as a data storage device known as a CD-ROM and to the media that can be written once and again and again (CD-R and CD-RW). CD-ROM and CD-R still widely used in the PC industry until the year 2006. Compact discs and other media development results achieved success in 2004. At that time the sales world for audio CDs, CD-ROM, and CD-R has reached approximately more than 30 billion pieces.