Jazz is a music genre originating in the African-American com communities of New Orleans. It started in the late 19th and early 20th century.
But in the 1960s, everything changed for jazz music. Those are the years musicians like Dizzy Gillespie and Billy Taylor started bands and groups. And those are the years we saw the best of musicians like Ella Fitzgerald, Louis Armstrong, Charles Mingus, Freddie Hubbard, Miles Davis, and more.
Jazz has all the elements that other music has, melody, harmony, and rhythm. What makes jazz different is the combination of rhythms from African and Latin American countries. But the coolest thing in jazz is the improvisation.