“You want a technical definition? Improvisation is in it, the Blues is in it, swingin' is in it.” — Wynton Marsalis

Lots of musicians improvise (shredding on the guitar). Improv doesn’t make it jazz.

Blues has some great improvising singers. Blues + improv doesn’t make it jazz.

Big bands can swing. But it can just be a performance. Without improvisation, its not jazz.

Spontaneous creation. Blues vocabulary. A swing rhythm. Anywhere all three are present, you’ve got jazz.