When playing in any of the 12 diatonic major keys on the guitar fretboard, there is always a fret position which has no notes belonging to that key. We can call that fret the "Chaos Fret". The origin of the word Chaos in Greek is chasm or void . In the Fretography ® method, I refer to that fret position as the Void Fret , but since this blog will approach the subject of the guitar from a more philosophical, rather than merely practical perspective, some new terminology seems in order. Let's regard the Chaos Fret as the starting position for exploring the fretboard. The 11th fret In the key of C comprising the notes; D#, G#, C#, F#, A# and D# — low to high. Of course these are the notes of the five black keys on the piano.