Top 40 is a music industry shorthand for the currently most-popular songs in a particular genre. When used without qualification it refers to the best-selling or most frequently broadcast popular music. The term is derived from record music charts, a few of which traditionally consist of a total of 40 songs. Top 40 is also an alternative term for the radio format of such music, also known as Contemporary hit radio.
The term "Top 40" for a radio format appeared in 1951. The Top 40, whether surveyed by a radio station or a publication, was a list of songs that shared only the common characteristic of being newly released. Its introduction coincided with a transition from the old ten-inch shellac 78 rpm record format for single "pop" recordings to the seven-inch vinyl 45 rpm format, introduced in 1949, which was outselling it by 1954 and soon replaced it completely. The Top 40 thereafter became a survey of the popularity of 45 rpm singles and their airplay on the radio.
By the late 1980s and the early 1990s, the 45 rpm record would decrease in popularity and other means would be used to evaluate the popularity of new songs, such as cassette-single, CD single, and digital MP3/AAC sales (plus radio airplay). Some disc jockeys of Top 40 and similar format programs have been implicated in various payola scandals.
Top 40 music charts and programs
The following run charts or programs consisting a total of forty tracks:
|American Top 40||radio airplay countdown|
|Ö3 Austria Top 40||airplay + sales chart|
|Dutch Top 40||airplay + sales chart|
|Los 40 Principales||Spanish chart|
|The Official Chart||UK sales + streaming chart on BBC Radio 1|
|The Net 40||a worldwide user generated Top 40 show|
- Pete Battistini, "American Top 40 with Casey Kasem The 1970s", Authorhouse.com, January 31, 2005. ISBN 1-4184-1070-5
- Susan Douglas, Listening In: Radio and the American Imagination (New York: Times Books, 1999)
- Durkee, Rob (1999). American Top 40: The Countdown of the Century. New York: Schriner Books. ISBN 0-02-864895-1.
- Fisher, Mark (2007). Something in the Air: Radio, Rock, and the Revolution That Shaped a Generation. New York: Random House. ISBN 0-375-50907-0.
- Ben Fong-Torres, The Hits Just Keep On Coming: The History of Top 40 Radio (San Francisco: Backbeat Books, 1998)
- Elwood F. 'Woody' Goulart, The Mystique and Mass Persuasion: Bill Drake & Gene Chenault’s Rock and Roll Radio Programming (2006)
- David MacFarland, The Development of the Top 40 Radio Format (New York: Arno Press, 1979)