Standards

• Compact Disc
  Compact Disc
  The Compact Disc is an optical disc used to store digital data. It was originally developed to store and playback sound recordings exclusively, but later expanded to encompass data storage , write-once audio and data storage , rewritable media , Video Compact Discs , Super Video Compact Discs ,...
  
  , an optical disc used to store digital data
• Red Book (CD standard), the original means of playing back audio on the medium
• 5.1 Music Disc
  5.1 Music Disc
  The DTS Music Disc , DTS Audio CD or 5.1 Music Disc is an audio Compact Disc that contains music in surround sound format. It is a predecessor of DVD Audio. Physically, it conforms to the Red Book standard, except for the way the music is encoded on the CD...
  
  , an extension to the red book standard that uses DTS Coherent Acoustics 5.1 surround sound
• Super Audio CD
  Super Audio CD
  Super Audio CD is a high-resolution, read-only optical disc for audio storage. Sony and Philips Electronics jointly developed the technology, and publicized it in 1999. It is designated as the Scarlet Book standard. Sony and Philips previously collaborated to define the Compact Disc standard...
  
  , a format which competes with DVD-Audio
• MP3 CD
  MP3 CD
  An MP3 CD is a Compact Disc that contains digital audio in the MP3 file format. Discs are written in the Yellow Book standard data format , as opposed to the Red Book standard audio format ....
  
  , a disc that contains MP3 files in Yellow Book format rather than converted from MP3 to Red Book format