Lester Young (1909–1959), tenor saxophonist nicknamed “Prez,” transformed jazz with an airy tone, buoyant swing and behind-the-beat phrasing. A cornerstone of Count Basie’s 1936–40 bands and small groups (Kansas City Six/Seven), he cut landmarks like “Lester Leaps In,” “Taxi War Dance” and “DB Blues.” His rapport with Billie Holiday and influence span generations.