Chords are made from scales.

     A scale is simply a row of notes in some consistent pattern. The word “scale” comes from a Latin word meaning “ladder” – notes ascend or descend the ladder rung by rung.  The most-used scale is the major scale, which is a row of notes in alphabetical rotation in the following pattern:
 

     Notice that the distance between the 1st and 2nd notes of the major scale is a whole step; between the 2nd and 3rd notes is a whole step; between the 3rd and 4th notes is a half step, and so on.

     For example, if we began our major scale on F sharp, it would look like this:

 

     If we started on B, it would look like this:
 

 

       Notice that the only half steps are between the 3rd and 4th notes and the 7th and 8th notes – all the other notes are separated by whole steps.
 

 

     In the preceeding chart, you will notice that there are no sharp scales listed. This is simply because D flat and C sharp are really the same key – just written differently. The same is true of E flat and D sharp, G flat and F sharp, A flat and G sharp, and B flat and A sharp. These are known as enharmonic scales – the sound is identical, but one scale is written as a flat scale while the other is written as a sharp scale.

     So melodies use scales, and like a climbing vine, they wrap themselves around the harmony of the song.

     Chords occur in different qualities. Three note chords are known as triads. There are four types of triads:
 

• Major

• Minor 

• Augmented

•  Diminished

     Major chords (triads) consist of a stack of 2 intervals: a major 3rd on the bottom, and a minor 3rd on top:

 

     Minor chords (triads) consist of a stack of 2 intervals: a minor 3rd on the bottom, and a major 3rd on top:

 

 

     Augmented chords (triads) consist of a stack of 2 intervals, both of which are major 3rds:

     Diminished chords (triads) consist of a stack of 2 intervals, both of which are major 3rds:

     Chords can be turned upside down: they are known as inversions. A chord with the name of the chord on the bottom is termed root position. A chord with the 3rd of the chord on the bottom is called 1st inversion, while a chord with the 5th of the chord as the lowest note is termed a 2nd inversion chord.

     Chords containing more than 3 notes are termed tetrads, but more commonly referred to as “4 note chords”, “5 note chords”, or "extended chords", because they extend beyond the mere triad. There are many extended chords, but here are some of the more common:

 

·         6th chords

·         Minor 6th chords

·         7th chords

·         Major 7th chords

·         9th chords

·         Major 9th chords (the "major" refers to the major 7th in the 9th chord)

·         11th chords

·         13th chords

 

    Chords can also be altered through the use of sharps and flats. For example, a 7th chord might be altered by lowering the 5th 1/2 step. It would be notated as a C7-5 chord. Another example would be a flat 9th chord, notated as C-9.

     Chords can also be used on top of a note which is not part of the chord. These are known as "slash chords" because they are notated like this: C/B   F7/G   etc.

     In addition to standard music notation, there is a "shorthand" kind of notation known as chord symbols. They typically are found above a melody line (tune of the song) and instruct the musician as to what chord to use at any given time:

     *It should also be noted that not all musicians agree on the names or symbols for all chords. There is no "authority" that passes down rules for such things; no congress that enacts laws about chords and how they are named. But there is general agreement on perhaps 90% of all chords; only on the more complex chords will you see much disagreement.

      In the charts below you will see some of the most common chords, all show in root position: