What is usually the most important characteristic of bebop music?

Bebop music is characterized primarily by its emphasis on fast tempos and complex chord progressions. This style emerged in the early 1940s, diverging from the more dance-oriented swing era that preceded it. Bebop musicians prioritized improvisation, often using intricate harmonies and rapid sequences that challenged traditional musical structures. The complexity of bebop is often reflected in its quick, nimble melodies and innovative rhythms, which demand a high level of technical proficiency from performers.

The focus on fast tempos is particularly notable as it distinguishes bebop from previous jazz styles, making it more of an intellectual listening experience rather than solely a source of dance. Bebop's complexity can be seen in the way musicians would often employ advanced harmonies and substitute chords that were not commonly used in earlier jazz. This marked a shift in jazz, emphasizing artistry and individual expression over commercial appeal and broad audience appeal.