The Harmonic Minor Scale

The Harmonic Minor Scale is commonly used by jazz musicians to improvise over a minor II V I. For example in the key of C minor we would play the C Harmonic minor scale to play over Dm7(b5) G7b9 and Cm (II V I in C minor). It is almost the same as the melodic minor scale but with a b6.  The scale is built on seven notes and its numeric formula is 1, 2, b3, 4, 5, b6, M7.