Diatonic harmony refers to the system of chords and melodies that are built using the notes from a specific scale, typically a major or minor scale. In this system, each note of the scale corresponds to a chord, creating a framework for musical composition. The chords are formed by stacking notes in intervals of thirds, resulting in a harmonious sound that is pleasing to the ear. This approach is foundational in Western music and is often used in genres like classical, jazz, and pop. Diatonic harmony emphasizes the relationships between the chords, allowing for smooth transitions and a sense of resolution within a piece.