Jazz: Old and New
Oftentimes jazz composers write a new tune that is based on an old tune - this is called a CONTRAFACT.
CONTRAFACT: a composition using a NEW melody over OLD harmony.
This came about in the 1940s as a result of composers wishing to perform tunes with a new flavor but familiar chords and also a desire to avoid copyright fees or violations (melody can be copyrighted; harmony cannot).
All of the pdf documents below feature the original tune along with a contrafact (a new melody over the original tune's harmony). Listen to the recordings!!