Pentatonic scales are very common in rock lead guitar playing. The scale is a great starting point to help getting comfortable writing and playing guitar solos. Almost every rock guitar solo utilizes it in some form or another. The purpose of this discussion is to serve as a starting point for learning and applying this great scale.
This harmonic minor scale is based on the natural minor scale with the same key / tonic note - A natural minor scale. Since the natural minor key is itself on the Circle of 5ths - A minor on circle of 5ths, this means that this is a commonly used harmonic minor scale key.
The natural minor scale can be thought of as a major scale with the 3rd 6th and 7th notes lowered by one half step. By altering these notes we also change the intervals which make up the scale. Also, most of the time when we refer to a ‘minor' scale we're generally referring to the natural minor.