Learning to apply the guitar number system to chord progressions will literally kick down the door to mastering the guitar fretboard.

The A minor pentatonic scale is one of the most widely used guitar scales of all, particularly in the blues genre. In this lesson we’ll take a deep dive into the scale and explore some examples of its many uses.

Below is a guitar chord key chart the major and minor keys. A chord key chart outlines the diatonic chords, or the chords that naturally occur in a given key. Chord charts are useful when trying to figure out the key of a song.

In this lesson we’re going to look at the application of the major scale by learning the Knockin’ on Heaven’s Door guitar solo by Slash of Guns N’ Roses.

In previous lessons we’ve learned about the CAGED system for learning guitar chords and scales. Another system that is useful for learning scales is the 3 notes per string system.