Trad jazz, short for "traditional jazz", is a form of jazz in the United States and Britain that flourished from the 1930s to 1960s, based on the earlier New Orleans Dixieland jazz style. Prominent trad jazz musicians such as Chris Barber, Freddy Randall, Acker Bilk, Kenny Ball, Ken Colyer and Monty Sunshine performed a populist repertoire which also included jazz versions of pop songs and nursery rhymes.

Dixieland jazz, also referred to as traditional jazz, hot jazz, or simply Dixieland, is a style of jazz based on the music that developed in New Orleans at the start of the 20th century. The 1917 recordings by the Original Dixieland Jass Band, fostered awareness of this new style of music.