CAGED Fretboard System
CAGED is a pattern-based system for learning all the scalar shapes of the guitar fretboard. Scales are typically played with the hands in a single position, that is, aligned with a particular group of frets. In the diatonic scale there are five such positions corresponding to five unique patterns of notes that are required to cover all possible patterns on the fretboard up to the twelfth fret. These five patterns make up the CAGED system and are named after the shapes of the chords of the same name played in the open position.
By learning the five CAGED patterns, any diatonic scale or mode can be played by simply transposing the shape to the correct position on the fretboard. If one knows the "C" shape for C major (which occurs in the open position), then one can play the same shape in F major simply by moving the hands up to the fifth fret position and playing the same pattern.
Several tunings and scales are implemented here. The main feature needing some explanation is the tritonic filter, which filters the scale down to its first, third, and fifth notes, so that the CAGED shape is more easily recognized.