John Birks "Dizzy" Gillespie ( ghil-ESP-ee; October 21, 1917 – January 6, 1993) was an American jazz trumpeter, bandleader, composer, educator and singer. He was a trumpet virtuoso and improviser, building on the virtuosic style of Roy Eldridge but adding layers of harmonic and rhythmic complexity previously unheard in jazz. His combination of musicianship, showmanship, and wit made him a leading popularizer of the new music called bebop. His beret and horn-rimmed spectacles, scat singing, bent horn, pouched cheeks, and light-hearted personality provided one of bebop's most prominent symbols.

In the 1940s, Gillespie, with Charlie Parker, became a major figure in the development of bebop and modern jazz. He taught and influenced many other musicians, including trumpeters Miles Davis, Jon Faddis, Fats Navarro, Clifford Brown, Arturo Sandoval, Lee Morgan, Chuck Mangione, and balladeer Johnny Hartman.

He pioneered Afro-Cuban jazz and won several Grammy Awards. Scott Yanow wrote, "Dizzy Gillespie's contributions to jazz were huge. One of the greatest jazz trumpeters of all time, Gillespie was such a complex player that his contemporaries ended up being similar to those of Miles Davis and Fats Navarro instead, and it was not until Jon Faddis's emergence in the 1970s that Dizzy's style was successfully recreated [....] Gillespie is remembered, by both critics and fans alike, as one of the greatest jazz trumpeters of all time".