As jazz continues to evolve, what becomes a standard in the jazz repertoire has also changed.
One of the most remarkable things about jazz in '40s and '50s was how musicians could appropriate a popular song and turn it into a jazz composition. It was a beautiful artistic juxtaposition - someone could hear a song sung in a film or on a Broadway stage, and then the same night hear that song turned into a bebop tour-de-force in an after-hours jazz club.
For instance, “You Stepped Out of a Dream” from the movie Ziegfield Girl becomes something altogether different when played by Sonny Rollins.
The tradition is still very much alive today. Lots of current players are treating rock songs like jazz standards.
Songs by the band Radiohead, for instance, have been covered by dozens of jazz instrumentalists, from Chris Potter to the Bad Plus.
Brad Mehldau Trio's version of Radiohead's "Everything in its Right Place" injects a new spontaneity and style while respecting the song's intimacy and aching beauty.