# Guitar/Chord Progressions

A knowledge of chord progressions will help you communicate and play
with other musicians. Knowing the most commonly used chord progressions
allows for greater enjoyment and unity when playing with other
musicians.

## The I-IV-V

The most common chord progression is I-IV-V. Note that Roman Numerals
are used to describe these chord progressions, where the \"I\" chord
stands for the chord on root note, the \"II\" for the chord on the
second note of the scale, and so on. Many songs use only these three
chords. If one views chords as a set of balancing scales with the root
note and octave root at opposing ends it will be noted that the IV and V
chords are at equal distance respectively to the root and octave root.
Take for example the key of C major:

**C - D - E - F - G - A - B - C**

You will see that the G note (or chord) is a fifth above the root note.
The note F is a fifth below the octave. This movement of a fifth is very
pleasing to the human ear in its sense of balance and cohesion in
relation to the root note. Another way to view chord progressions is
that of a journey. In the sense that the root (or tonic) chord is the
starting point and the octave root is at the end. All other points
(chords) provide interest and variation with the fourth and the fifth
chord occupying a special place on the journey due to them being
half-way.

Many chord progressions start at the tonic (I), moves away to somewhere
else, only to come back to the tonic. You can play this progression with
major chords or you can substitute minor chords for the IV or V.

### Applying the I-IV-V

Eddie Cochran and Buddy Holly are two artists who have used this
progression extensively. Note that this chord progression uses a V7
chord. A V7 chord is just a V chord with an extra note. It is so common
a device that when learning a chord progression many guitarist will play
it through a few times using I-IV-V (normal V chord with no extra note)
and then will play the chord progression I-IV-V7 a few times before
switching back to the normal I-IV-V.

```{=html}
<div style="font-family:'Courier New'">
```
<File:E> major chord.svg\|**E major (I)** <File:A> major chord.svg\|**A
major (IV)** <File:B7> chord.svg\|**B7 (V7)**

```{=html}
</div>
```
## I-vi-IV-V

This progression is commonly referred to as the 50\'s progression,
because it was common to many of the popular songs of the 1950\'s,
notably \"Stand by Me\". Note that the vi chord is a tonic extension, as
it contains many of the same notes as the tonic (I) chord. You may see
this progression with sevenths added in a blues song (e.g., G7, e min 7,
C7, D7). Here is the progression in the key of G major.

```{=html}
<div style="font-family:'Courier New'">
```
<File:Gmaj> chord.svg\|**G major (I)** <File:Em> chord.svg\|**E minor
(vi)** <File:Cmaj> chord.svg\|**C major (IV)** <File:Dmaj>
chord.svg\|**D major (V)**

```{=html}
</div>
```
## The I-V-I-I

This is a popular progression at the beginning of a much larger line,
and can be combined with many other scale degrees.

## II-V-I

As its name indicates, the progression is: IImin7, V7 and Imaj7. In a
pop song, the chords might be IImin, V7, IMaj, with the first and last
chord being three-note chords (triads). In jazz, all three chords are
usually seventh chords. The II/V/I is important in jazz, where some
songs have the progression in a number of keys.

```{=html}
<div style="font-family:'Courier New'">
```
<File:Dm7> chord.svg\|**Dm7 (ii-min7)** <File:G7th> chord.svg\|**G7
(V7)** <File:C> maj7 chord.svg\|**Cmaj7 (I)**

```{=html}
</div>
```
Alternatively you can change the chord type on the II, and alter the
voicing of the V. Some examples are:

-   IIm7b5(9)/V7alt /Imaj7

(with a V7alt, the performer alters the 9th to b9 or #9 and/or makes the
11 into #11 and/or makes the 13 into b13)

### Applying the II-V-I

II-V-Is can be chained together, creating complex progressions. Here\'s
an example that starts in C major and moves to the relative minor, a
minor:

```{=html}
<div style="font-family:'Courier New'">
```
<File:Cmaj> chord.svg\|**C major (I)** <File:Bm7b5> chord.svg\|**Bm7b5
(II)** <File:E7> chord.svg\|**E7 (V)** <File:Am7> chord.svg\|**Am7 (I)**
<File:Dm7> chord.svg\|**Dm7 (II)** <File:G7th> chord.svg\|**G7 (V)**
<File:C> maj7 chord.svg\|**Cmaj7 (I)**

```{=html}
</div>
```
```{=html}
<div style="font-family:'Courier New'">
```
` C      Bm7b5 E7   (I     ii  V)`\
` Am7    Dm7   G7   (I     ii  V)`\
` C      (etc...)   (I     etc..)`

```{=html}
</div>
```
An example of complicated progression that can be created this way is
the \"Coltrane Changes\", where the
\"I\" chords move by Major 3rd intervals. Here\'s a simple example:

```{=html}
<div style="font-family:'Courier New'">
```
` Dm7  G7  Cmaj7    (ii V I  )`\
` F#m7 B7  Emaj7    (ii V I  )`\
` Bbm7 Eb7 Abmaj7   (ii V I  )`\
` Dm7  etc...       (I etc...)`

```{=html}
</div>
```
The way the ii-V-I progression works is first that it moves by 4ths
upwards, which very often produces interesting results, and the 7th goes
down a half tone below and becomes the following chord\'s 3rd.

## Minor ii-V-i

Another commonly used chord progression is the minor ii-V-i. One can
derive this from the melodic minor scales shown above, while
substituting a IminMaj7 for the IMaj7 chord, or by using three
modes "wikilink") from one harmonic minor
scale , which produces the
following chord progression:

-   ii m7 b5/ V7 / i

In the key of c minor, this would be:

-   d m7 b5/ G 7 / c min

