John Birks "Dizzy" Gillespie (October 21, 1917 – January 6, 1993) was an American jazz trumpeter, bandleader, composer and occasional singer. Gillespie was a trumpet virtuoso and improviser, building on the virtuoso style of Roy Eldridge but adding layers of harmonic complexity previously unknown in jazz. His beret and horn-rimmed spectacles, his scat singing, his bent horn, pouched cheeks and his light-hearted personality were essential in popularizing bebop. In the 1940s Gillespie, together 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, Fats Navarro, Clifford Brown, Arturo Sandoval, Lee Morgan, Jon Faddis and Chuck Mangione.