The Minor Seventh Chord is a minor triad to which a minor seventh is added. The notes are: root, minor third, perfect fifth, and minor seventh. Its sound is 'melancholic', 'soft', and 'relaxed', and unlike the minor seventh of the Dominant 7, it does not have a strong resolving tension. It is extremely common in jazz, soul music, and R&B, where it functions as a tonic chord (i degree) in minor keys or, more frequently, as a subdominant chord (ii degree) or minor chord on the third or sixth degree in major keys (iii7, vi7). It is considered a 'stable' chord within a jazz context, and is an essential component of the ii-V-I progression, providing the basis for subsequent tension and resolution.