William John Evans was an American jazz pianist and composer who worked primarily as the leader of his trio. His interpretations of traditional jazz repertoire, his ways of using impressionist harmony and block chords, and his trademark rhythmically independent, "singing" melodic lines, continue to influence jazz pianists today.

Jazz piano is a collective term for the techniques pianists use when playing jazz. The piano has been an integral part of the jazz idiom since its inception, in both solo and ensemble settings. Its role is multifaceted due largely to the instrument's combined melodic and harmonic capabilities. For this reason it is an important tool of jazz musicians and composers for teaching and learning jazz theory and set arrangement, regardless of their main instrument. By extension the phrase 'jazz piano' can refer to similar techniques on any keyboard instrument.