Optical audio disc

An audio optical disc is an optical disc that stores sound information such as music or speech. It may specifically refer to:

Audio CDs

 * Compact disc (CD), an optical disc used to store digital data (700 MB storage)
 * Compact Disc Digital Audio (CD-DA), a CD that contains PCM encoded digital audio in the original "Red Book" CD-DA format
 * 5.1 Music Disc, an extension to the Red Book standard that uses DTS Coherent Acoustics 5.1 surround sound
 * Compressed audio optical disc, an optical disc storing MP3s and other compressed audio files as data, rather than in the Red Book format

Audio DVDs

 * DVD, 4 GB single layer, 8 GB double layer storage
 * DVD-Audio, a DVD that plays audio
 * Super Audio CD (SACD), a format which competes with DVD-Audio

Audio Blu-rays

 * Blu-ray, 25 GB single layer, 50 GB double layer
 * BD-Audio, a Blu-ray disc that is capable of audio-only playback