A pentatonic scale contains five different notes in each octave instead of the seven of the major and minor scales. The most widespread form has no semitones at all: the major pentatonic in C is C–D–E–G–A, and the same notes starting on A give the minor pentatonic, A–C–D–E–G. The five black keys of the piano form a pentatonic scale too, which is why simply playing on them always sounds pleasant.
Pentatonic scales occur in a remarkable range of traditions, from Chinese and Javanese music to sub-Saharan African, Native American and European folk melodies; in the twentieth century composers such as Debussy also used them. With no semitone clashes, almost any order of notes sounds consonant, which makes the scale a favourite for improvisers and for the simple, singable melodies of jazz lo-fi, where soft pentatonic motifs on keys or guitar float above the chords.