Jazz music is known as the only art form to originate in the Unite States, Jazz began in the late 1800s. Jazz grow from a combination of influences such as black American, African rhythms, American band tradition, slavery. Most of the best jazz music is writing and performed in the Unite states. But, the other country have made a great contribution to jazz music and looked at it as an art form before it gained recognition in the Unite States.
One key to jazz is called improvisation- the ability to create music run up and down the scale. While playing jazz you have a change to express feeling through improvising, you play a role as a soloist from just a regular player in the group. Improvising give a fresh sound each time you play a tune whether it's the same tune or a different one the sound will be a sense of excitement at each performance.
Black Americans who had no training in the western music performed the earliest jazz; they had a strong musical culture from black life. If you look at the roots of jazz, you go back to the 1800s where black people songs and dance on the plantation. During slavery in the 1700s and 1800s black sang and hums in the fields while picking cotton, vegetable and cutting wood, what ever they had to do for that day.
Ragtime was style that jazz player was influenced by early in their music. This style began in the area of St. Louis in the late 1890s. This style became one of the most popular style to jazz player; Ragtime was an energetic and syncopated variety of music.
(Information: African Americans (article) world book online)