How many kinds of chords are there?

***14 types. They are the triad, the seventh chord, the dominant fourth and sixth chord, the second sixth chord, the major second chord, the major third chord, the major sixth chord, the first seventh chord, the minor fourth chord, the fifth augmented third chord, the descending sixth chord, the descending seventh chord, the descending third chord, and the descending second chord.

1. The triad

The chord in which three notes are placed in a triadic relationship is called a triad. The tones of a triad are called root, third and fifth from the bottom up, and are labeled with 1, 3 and 5 respectively.

2, seventh chord

The chord that consists of four tones superimposed in a relationship of thirds is called a seventh chord. The tones of a seventh chord are called root, third, fifth and seventh from the bottom up, and are labeled 1, 3, 5 and 7 respectively.

3. Secondary hexachord

The secondary hexachord is the first inversion of the secondary chord, Dm/F in the key of C. Its constituent tones are FA, LA, RE. You will notice that it is only one tone away from the F chord (the fourth chord), which is FA, LA, RE, and the latter is FA, LA, DO.

4. Major secondary chord

This is actually an out-of-tune chord. This is actually an off-key chord, but I won't illustrate the point from that perspective here. A major secondary chord is a secondary chord in the ascending triad, and in the key of C major it's a 2, #4, 6 chord. It is characterized by a strong tendency toward the genitive chord (the fifth chord), which is to say that it constitutes a D-G progression in the key of C major.

5. Major triad

This is also an off-key chord. In the key of C major it is the E chord, 3-#5-7. It is formed by the elevated triad of the triad Em. It tends to the sixth degree chord Am, which is what forms the E-Am progression in C major.