Major chords have a bright, happy sound. They are typically made up of a root note, a major third, and a perfect fifth. For example, the C major chord is made up of the notes C, E, and G.
Minor chords have a sad, dark sound. They are typically made up of a root note, a minor third, and a perfect fifth. For example, the C minor chord is made up of the notes C, Eb, and G.
The difference between a major chord and a minor chord is the interval between the root note and the third note. In a major chord, the interval between the root note and the third note is a major third. In a minor chord, the interval between the root note and the third note is a minor third.
Major and minor chords are used in a wide variety of music genres, from classical music to pop music. They can be used to create a variety of moods and atmospheres.