There are many different types of chord progressions, from simple major and minor chord progressions to more complex ones such as those used in jazz. Simple chord progressions generally revolve around the first, fourth and fifth chords in any given key, and more complex progressions make use of other notes such as the seventh. Other complex chord progressions can use chords such as suspended chords and diminished chords.
Chord progressions are formed from music theory, which is a purely theoretical way to compose and think about music. In music theory, the notes in the key are numbered from one to seven, and this number system can be applied to any key. The key of C major, for example, is numbered from one to seven in that order. The first, fourth and fifth notes are generally thought to sound good together for a chord progression.
Musical chords can belong to one of many different types. The basic chord types are major and minor chords, which are considered to sound “happy” and “sad,” respectively. Major chords are formed from the first, third and fifth notes, with an additional, higher first added on.
Minor chords have a flattened third. There are also seventh chords, which incorporate the musical seventh note, and suspended chords, which replace the third with a second or fourth. Many other different types of chords exist.
In most chord progressions, the first, fourth and fifth are major chords, and the second, third and sixth are minor chords. The seventh chord is a diminished chord. The most basic of all chord progressions goes from the first to the fourth and then to the fifth. A simple minor chord progression goes from the sixth to the second and then the third. These can also be mixed up, however; for example, a chord progression could go from the first to the sixth, then the fourth and the fifth.
More complex progressions can replace the fifth with the seventh, or even replace the first with the third. These create different sounds and can be used to produce more interesting songs. For example, replacing the first with the third is often done in jazz chord progressions.
Blues chord progressions are usually based around the “12 bar blues,” which features four bars of the first, two of the fourth, two of the first, one of the fifth, one of the fourth, and two of the first. In blues, the use of seventh chords is also common. It is also important to remember that although music theory is often used to compose chord progressions, its rules can also be bent by the musician.