The pianist and bandleader Count Basie had a major impact on the world of jazz for almost 50 years. As a pianist, his unique, sparse style of "comping" and "filling" behind soloists or ensembles in the big band era became the model from which many other pianists developed their own styles in the revolutionary age of bebop. The definition of roles in Basie's rhythm section, and its clean, unhurried sound, also provided a model for subsequent innovations.