The question of the origin of the word jazz has resulted in considerable research, and its history is well documented. It is believed to be related to jasm , a slang term dating back to 1860 meaning "pep, energy."  The earliest written record of the word is in a 1912 article in the Los Angeles Times in which a minor league baseball pitcher described a pitch which he called a jazz ball "because it wobbles and you simply can't do anything with it." 
Jazz originated in the late 19th to early 20th century as interpretations of American and European classical music entwined with African and slave folk songs and the influences of West African culture.  Its composition and style have changed many times throughout the years with each performer's personal interpretation and improvisation, which is also one of the greatest appeals of the genre. 
By 1866, the Atlantic slave trade had brought nearly 400,000 Africans to North America.   The slaves came largely from West Africa and the greater Congo River basin and brought strong musical traditions with them.  The African traditions primarily use a single-line melody and call-and-response pattern, and the rhythms have a counter-metric structure and reflect African speech patterns.