Jazz is an original American art form that began in the southern United States in the early 20th century.
Three basic elements set this art form apart from classical music:
1) Rhythm
2) Improvisation
3) Conversation
Using words to describe the improvised conversation between the two musicians might seem like this:
Trumpet player: That pizza was delicious.
Piano player: Yeah man, delicious.
Trumpet player: Delicious and hot!