Muzak is a brand of background music played in retail stores and other public establishments. In 1981, Westinghouse bought the company and ran it until selling it to the Fields Company of Chicago, publishers of the Chicago Sun-Times, on September 8, 1986. Formerly owned by Muzak Holdings, the brand was purchased in 2011 by Mood Media in a deal worth US$345 million.

The word Muzak has been a registered trademark since December 21, 1954, of Muzak LLC, although it dominated the market for so many years that the term is often used (especially when used with lowercase spelling) as a generic term for all background music. The term Muzak is – at least in the United States – often used as a term for most forms of background music, regardless of the source of the music, and may also be known as "elevator music" or "lift music".

Though Muzak Holdings was for many years the best-known supplier of background music, and is commonly associated with elevator music, the company itself did not supply music to elevators. Since 1997, Muzak has used original artists for its music source, except on the Environmental channel.

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