The basic chords of music are TRIADS - 3-note chords composed of various intervals of the scale based on the root, 3rd, and 5th and their alterations. To form a 4-note chord you simply add a note of the scale such as the 6th, 7th, or major 7th to the basic triad. This short video demonstrates how this works:

For a COMPLETE course in chords click on “All The Chords In The Whole Wide World!”

Perhaps the most useful kind of chord is the 7th chord, partly because there are so many variations of 7ths. Far and away the most-used 7th chord is the dominant 7th, notated as F7, Bb7, D7, etc. But there are also at least 6 other types of 7th chords, including maj7, dim7, aug7, m7, etc. Watch this short video and you’ll get the idea:

7th chords are wonderful and satisfying, but at the same time they can be kind of confusing since there are so many different types of seventh chords. The most common type is the dominant 7th chord — usually just refered to as a “7th”. Then there is a major 7th chord, a minor 7th chord, a diminished 7th chord, a half-diminished 7th chord, an augmented 7th chord, etc, etc.

Watch this short video and hopefully it will clear up the confusion somewhat:

Piano chords come in all flavors — major, minor, diminished, augmented, and many kinds of extended chords such as 6ths, 7ths, 9ths, 11ths, 13ths, etc. This 50-minute video will give you a good introduction to piano chords and prepare you for more in-depth study:

Chords of all kinds: Major, minor, diminished, augmented & extended chords from chordman on Vimeo.

There are several different kinds of 7th chords. This video is a summary of previous videos where we examined each type in detail.

Seventh chords are some of the most useful and interesting chords one can play on the piano. Watch this short video and see the difference between a 7th chord, a maj7th chord, a min7th chord, etc.