CD

The compact disc, or CD, is a digital optical disc format for storing and playing back digital audio and other data, built around the CD-DA standard for uncompressed stereo audio. It was developed jointly by Philips and Sony, with engineers including Kees Schouhamer Immink and Toshitada Doi leading the work, and was first released in Japan in October 1982 before reaching North America and Europe in March 1983, becoming the second optical disc format to reach the market after LaserDisc. A standard disc is 120 millimeters across and 1.2 millimeters thick, holding 74 to 80 minutes of audio or roughly 650 to 700 mebibytes of data. More than 200 billion CDs had been sold worldwide by 2007, and the format's US music market share peaked at 92.3 percent around 2000 before MP3s, digital downloads and streaming drove its decline from the mid-2000s onward. This description is adapted from Wikipedia contributors under CC BY-SA 4.0; changes were made. https://creativecommons.org/licenses/by-sa/4.0/