A Compact Disc (CD) is a digital optical disc used to store data, primarily music. Introduced in the early 1980s, CDs revolutionized the way people listened to music, offering better sound quality and durability compared to vinyl records and cassette tapes. A standard CD can hold up to 700 megabytes of data or about 80 minutes of audio.
CDs are read by a laser in a CD player, which interprets the digital information encoded in tiny pits on the disc's surface. Over time, CDs have also been used for data storage in computers, leading to the development of CD-ROMs for software and other digital content.