A blue note is a pitch bent below its normal position in the major scale, most often the third and the seventh degrees and sometimes the fifth. In the key of C that means notes around E♭, B♭ and G♭, though singers, guitarists and horn players often aim between the flat and natural pitch, sliding into or out of it. Britannica traces this expressive bending to pitch inflections found in many West African languages and musical forms, which shaped the blues in the United States.
Blue notes give the blues its characteristic ache and are a basic ingredient of jazz phrasing. On a fixed-pitch instrument such as the piano, which cannot bend notes, players often suggest them by moving quickly between neighbouring keys. In jazz lo-fi they appear in sampled saxophone and guitar phrases and in short keyboard licks. The term should not be confused with Blue Note Records, the jazz label founded in 1939.