The major pentatonic scale uses only five notes taken from the major scale: the first, second, third, fifth, and sixth degrees, omitting the fourth and seventh. C major pentatonic is therefore C D E G A. This scale has a bright, open sound free of half-step clashes, which is why it appears so widely in folk, pop, country, and gospel music. The G major pentatonic scale, for example, consists of G A B D E, omitting the fourth (C) and seventh (F♯) from the G major scale; it is extremely popular for guitar and piano improvisation.
The minor pentatonic scale similarly uses five notes: the first, lowered third, fourth, fifth, and lowered seventh degrees of the major scale. A minor pentatonic is A C D E G, for instance. This scale is the foundation of blues, rock, and many improvisational styles because its intervals produce a powerful, instantly recognizable sound that works over a wide variety of chord progressions. The major and minor pentatonic scales are relatives of each other in exactly the same way as the major and natural minor scales. C major pentatonic (C D E G A) contains the same notes as A minor pentatonic (A C D E G), just starting on a different note.
The blues scale adds a single chromatic note to the minor pentatonic: the lowered fifth, often called the blue note. The A blues scale is therefore A C D E♭ E G, where the E♭ sits between the fourth and fifth degrees. This added passing tone gives the scale its characteristic bluesy, soulful quality and is the source of the expressive bends and slurs heard in blues and rock solos.
The chromatic scale consists of all twelve notes in succession, each separated by a half step. On the piano, this means playing every white and black key in order without skipping any. Unlike diatonic scales, the chromatic scale is not associated with any particular key. A common right-hand fingering for the chromatic scale follows the black-key groupings: use fingers 1 and 3 on the group of two black keys and fingers 1, 2, and 3 on the group of three black keys, with the thumb always landing on white keys. To develop evenness, the chromatic scale should be practiced slowly with a metronome, focusing on smooth thumb crossings and keeping the fingers close to the keys, gradually increasing speed only after clean, even playing is achieved.