cover image

Compact disc

Digital optical disc data storage format / From Wikipedia, the free encyclopedia

Dear Wikiwand AI, let's keep it short by simply answering these key questions:

Can you list the top facts and stats about CD?

Summarize this article for a 10 year old

SHOW ALL QUESTIONS

The compact disc (CD) is a digital optical disc data storage format that was co-developed by Philips and Sony to store and play digital audio recordings. In August 1982, the first compact disc was manufactured. It was released in October 1982 in Japan and branded as Digital Audio Compact Disc.

Quick facts: Media type, Encoding, Capacity, Read mec...
Compact disc
Compact_Disc_wordmark.svg
Audio_Compact_Disc.png
The readable surface of a compact disc includes a spiral track wound tightly enough to cause light to diffract into a full visible spectrum.
Media typeOptical disc
EncodingVarious
CapacityTypically up to 700 MiB (up to 80 minutes audio), 800 MiB (also up to 90 minutes audio), 870 MiB (and up to 99 minutes audio)
Read mechanism780 nm wavelength, 800 nm wavelength, 870 nm wavelength (infrared and red edge) semiconductor laser (early players used helium–neon lasers),[1] 1,200 Kbit/s (1×)
Write mechanism780 nm wavelength, 800 nm wavelength, 870 nm wavelength (infrared and red edge) semiconductor laser in recordable formats CD-R and CD-RW, pressed mold (stamper) in read only formats
StandardRainbow Books
Developed byPhilips, Sony
DimensionsDiameter: 120 mm (4.7 in)
Thickness: 1.2 mm (0.047 in)
UsageAudio and data storage
Extended fromLaserDisc
Extended to
Released
  • October 1982; 41 years ago (1982-10) (Japan)
  • March 1983; 40 years ago (1983-03) (Europe and North America)
[2]
Close

The format was later adapted (as CD-ROM) for general-purpose data storage. Several other formats were further derived, including write-once audio and data storage (CD-R), rewritable media (CD-RW), Video CD (VCD), Super Video CD (SVCD), Photo CD, Picture CD, Compact Disc-Interactive (CD-i), Enhanced Music CD, and Super Audio CD (SACD) which may have a CD-DA layer.

Standard CDs have a diameter of 120 millimetres (4.7 in) and are designed to hold up to 74 minutes of uncompressed stereo digital audio or about 650 MiB (681,574,400 bytes) of data. Capacity is routinely extended to 80 minutes and 700 MiB (734,003,200 bytes) by arranging data more closely on the same-sized disc. The Mini CD has various diameters ranging from 60 to 80 millimetres (2.4 to 3.1 in); they are sometimes used for CD singles, storing up to 24 minutes of audio, or delivering device drivers.

At the time of the technology's introduction in 1982, a CD could store much more data than a personal computer hard disk drive, which would typically hold 10 MiB. By 2010, hard drives commonly offered as much storage space as a thousand CDs, while their prices had plummeted to commodity levels. In 2004, worldwide sales of audio CDs, CD-ROMs, and CD-Rs reached about 30 billion discs. By 2007, 200 billion CDs had been sold worldwide.[3]

Oops something went wrong: