Gillespie was a trumpet virtuoso and gifted improviser. In addition to his instrumental skills, Dizzy's beret and horn-rimmed specs, his goofy scat singing, his bent horn and pouched cheeks, and his light-hearted personality put a human face on what many, including some of its creators, regarded as threatening and frightening music. In his playing, Gillespie built on the "saxophonic" style of Roy Eldridge and then went far beyond it.
In addition to his work with Parker, Gillespie led small combos and big bands and appeared frequently as a soloist with Norman Granz's Jazz at the Philharmonic. Early in his career, he appeared with Cab Calloway, who fired him for playing "Chinese music". The legendary big band of Billy Eckstine gave those unusual harmonies a better setting. In the 50s, Gillespie led the movement called Afro-Cuban music, bringing Latin and African elements to greater prominence in jazz and even pop music, particularly salsa.
Gillespie wrote a number of songs, notably "Manteca", "A Night in Tunisia", "Birk's Works", and "Con Alma", all jazz classics.
Cheek distention is purportedly called "Gillespie's pouch" in the medical community.
Dizzy Gillespie was one of the most famous adherents of the Bahá'í Faith to the point that he is often called the Bahá'í Jazz Embassador.