One way we organize our mental map of the guitar is to use movable chord forms. Forms are chord shapes that lend their architecture to the other 11 tones (positions). There are 5 basic chord forms: CAGED. We could organize chord forms around different chords, yet the chords C, A, G, E, and D provide a great combination of complete fretboard mapping.

Small numbers next to fret numbers are fingers. x = mute with fretting hand thumb over top of neck.
First, we get these basic chords in our hands. Fret each of them, making sure that all of the open strings are ringing clearly.
A, G, E, D, & C are common and not too difficult. Once we have them, we will then base other chords on them by moving each one up the fretboard. There are a number of other ways to finger these chords. The fingerings shown on the grids are one way to fret these chords.

The wavy lines are muted strings. The double dot is the root.
When a chord moves up the neck, the index finger is responsible for 'closing' the previously open strings.
For the C Form, we can 'eliminate' the first string so we don't have to bar. We could also include the bar. As shown in the D chord above, we can also eliminate the lowest root on the 5th string, & just fret the 4, 3, & 2 strings. This is a useful fragment [part of a chord using less than all 6 strings] for this chord shape. And, the 5th string could be left open at the frets indicated above, for some cool resonance.
As we build our chord vocabulary (fretted library), we are looking for resonance. For a given situation, is this version of this chord offering enough resonance? Is it an appropriate voicing? And, different style use different types of voicings.
Since there are 12 tones, every shape, form, or pattern, etc. can be moved to each of these tones. We will refer to this as 12 for 1. We know one thing that can be moved to 12 positions. This is good mileage and a reason that the CAGED system is okay with us. Once you know all 5 and can move them to 12 position, this is 60 chords. Once we consider fragments and adding open strings to them, the number of chords we know grows exponentially.


Double shapes are borders (shared tones) between chord forms.
The CAGED guitar architecture provides a template for learning all of the possible fingerings for any type of chord. In this lesson, we will look at the linear cycle of chord forms for the C Major chord. We have dropped some tones in some forms to make the fingerings easier.

C begins is own cycle, and we can see its fretted version 12 frets higher on the first fretboard layout above.
R, 3, and 5 are indicated on the edge of each form above. You will want to memorize the chord components, so when we modify new types of chords to these, we know where the Root, the 3rd, and the 5th are located.
It is also good to notice the shared borders. Take a look at the G and A forms. We can clearly see that they share a 3 string bar on strings 4, 3, and 2. Like pentatonics, borders are where forms share common tones.
Whichever form originates the system at the nut begins the cycle...since C begins the cycle for C, the next form will be A, then, G, etc. The linear cycle always goes in word order C-A-G-E-D. We can compare this to a loaf of bread, where one of the forms is the heel of the loaf. Once the heel is recognized, the other slices (forms) always go in the same word order.
| CAGED Form | The Heel for... |
| C | C, Db |
| A | A, Bb, B |
| G | G, Ab |
| E | E, F, F# |
| D | D, Eb |