One of the consummate pianists and singers of his time, Fats Waller was in on the ground floor of jazz. From his teens in the 1910s to his death in 1943, he developed forward-thinking techniques. His dexterity as a singer (“A Porter's Love Song to a Chambermaid”), as well as his elegance and intimacy in duetting with other vocalists (“I Can't Give You Anything but Love”), laid groundwork for the improvisations of the '50s and '60s.