The first CDs were available in October 1982. In 1985, the first CD-ROMs, which are read by computers, came to the market. Since that time, more than 30 billion CDs have been sold.
Compact discs use microscopic grooves that can be read by a laser. Because lasers are far more precise than the needles used on vinyl records, they can store far more audio and data than vinyl albums, and their superior sound and practicality make them preferable to music tapes. While digital distribution has partially supplanted CDs, they remain the top choice for people who want a physical copy of their music.