Harmony is the lesson that examines in detail everything related to chords, that is, how they are formed and how they connect to one another.

It is known from Music Theory that there are four types of chords: major, minor, diminished, and augmented. The major and minor are called consonant and can stand alone. All the others are called dissonant and require a continuation or, as we say, a resolution. The most important chord is the tonic chord (I) and all others lead to it, sooner or later.