Traditional jazz
From Conservapedia
Traditional jazz is a term loosely employed to describe any form of jazz that predates the Swing era.
Rhythmically, it is characterised by a rather literal 4/4 beat in comparison to a Swing 4/4, where the first beat is de-emphasised.
It evolved from ragtime and blues rhythms in New Orleans, and its first master was arguably King Oliver, whose beautiful ensemble recordings epitomise the early collective ethos of the music.
Later on, Louis Armstrong began to evolve an approach in which solo instruments would predominate, while Jelly Roll Morton became the first great arranger of jazz.