Do you listen to jazz music? It originated in the African American communities, but is enjoyed by many cultures.
I heard that it was a cross  of african american and european american styles.  How long has jazz been around?
Since the late 19th and early 20th centuries. It's been around for a long time.
When i go to New Orleans, they have bands roaming the streets.  Is that Jazz and why do they play jazz there, besides it being old fashioned?
It is because that is actually where jazz originated, in the black communities of New Orleans.