I-IV-V

The I-IV-V chords are a common sequence used in many songs across various musical styles. They refer to three chords built on specific notes of a scale: the I chord (tonic) is the main home note, the IV chord (subdominant) adds a sense of movement away from the home, and the V chord (dominant) creates tension that naturally resolves back to the I chord. For example, in the key of C major, these chords are C (I), F (IV), and G (V). This progression provides a familiar, pleasing harmonic foundation that shapes the structure of many melodies and harmonies.