But minor chords also occur frequently in songs which are written in major keys, and they provide the contrast needed to make a song interesting. The most-used chords in any given key are the I, IV, and V chords which are major, but followed by the ii, iii, and iv chords which are minor. So most songs written in a major key include from 1 to 3 minor chords somewhere along the line.

To understand minor chords we first need to understand major chords. Major chords are created using the root, 3rd, and 5th of a major scale. A major scale (from "la scala" = the ladder) is defined as a row of notes that moves from a root (the bottom or starting note) and moves upward by 2 whole steps, a half step, 3 whole steps, and one half step until it reaches the octave note (8 notes higher). By selecting the root, 3rd, and 5th notes of the scale we create a major chord (also known as a triad -- a 3-note chord).

There are only 12 different major chords:

3 of the major chords were made of all white keys: C F G.

3 of the major chords were made of white keys on the outside, with a black key in the middle: D E A. 3 of the major chords were like an Oreo cookie? Black on the outside, white on the inside: Db Eb Ab.

That only leaves 3 major chords, one of which is all black, and one of which is white, black, black, and the other the reverse -- black, white, white. Gb (all black) B (white, black, black) Bb (black, white, white).

And that's it.

Here they are in that order:

Major chords composed of all white keys:

C major chord: C, E, G
F major chord: F, A, C
G major chord: G, B, D

Major chords composed of white keys on the outside with a black key in the center:

D major chord: D, F#, A
E major chord: E, G#, B
A major chord: A, C#, E

Major chords composed of black keys on the outside with a white key in the center: Db major chord:

Db, F, Ab
Eb major chord: Eb, G, Bb
Ab major chord: Ab, C, Eb

Major chords left over:

Gb major chord (all black keys): Gb, Bb, Db
Bb major chord: Bb,
D, F B major chord: B, D#, F#

All these chords shown above are in "root position"; that is, the root, or name of the chord, is on the bottom of the chord. In a subsequent article we will take up the other positions in which we can play chords: inversions.

So why do I need to learn the major chords?

The answer is simple: all other chords are formed by altering one or more notes of a major chord. So once you know major chords, it's easy to find minor, diminished, augmented, and extended chords.

So to find a minor chord, all we need to do is lower the 3rd of each chord 1/2 step. So to make the C major chord into a C minor chord, we just need to lower E (the 3rd of the chord) 1/2 step to Eb.

So C minor chord is C, Eb, G

Here are the rest of the minor chords:

F minor chord: F, Ab, C
G minor chord: G, Bb, D
D minor chord: D, F, A
E minor chord: E, G, B
A minor chord: A, C, E
Db minor chord: Db, Fb, Ab (Fb is the same as E)
Eb minor chord: Eb, Gb, Bb
Ab minor chord: Ab, Cb, Eb (Cb is the same as B)
Gb minor chord: Gb, Bbb, Db (Bbb is the same as A)
B minor chord: B, D, F#
Bb minor chord: Bb, Db, F

Learn them well, as you will be playing them all of your life in countless songs.