name a few famous musicians associated with this kind of musical style?
Bessie Smith, King Oliver,  Bill Johnson to name a few.
Jazz
In 1919, Kid Ory's Original Creole Jazz Band of musicians from New Orleans began playing in San Francisco and Los Angeles, where in 1922 they became the first black jazz band of New Orleans origin to make recordings. During the same year, Bessie Smith made her first recordings. Chicago was developing "Hot Jazz", and King Oliver joined Bill Johnson. Bix Beiderbecke formed The Wolverines in 1924.
who is usually considered the first important composer of american popular song Stephen Foster. when was this kind of music first recorded? 1917 - 1920's. what kind of music does it include? Ragtime, Blues, Jazz, Swing, Rock to name a few. what race is the third kind of musical style associated with? African-American. has this kind of musical style changed or evolved? Yes, as jazz spread around the world, it drew on national, regional, and local musical cultures, which gave rise to different styles.
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Jazz [SEP] The Jazz Age
In 1919, Kid Ory's Original Creole Jazz Band of musicians from New Orleans began playing in San Francisco and Los Angeles, where in 1922 they became the first black jazz band of New Orleans origin to make recordings. During the same year, Bessie Smith made her first recordings. Chicago was developing "Hot Jazz", and King Oliver joined Bill Johnson. Bix Beiderbecke formed The Wolverines in 1924. Despite its Southern black origins, there was a larger market for jazzy dance music played by white orchestras. In 1918, Paul Whiteman and his orchestra became a hit in San Francisco. He signed a contract with Victor and became the top bandleader of the 1920s, giving hot jazz a white component, hiring white musicians such as Bix Beiderbecke, Jimmy Dorsey, Tommy Dorsey, Frankie Trumbauer, and Joe Venuti.