The diatonic major scale is the most important in Western music. The major characteristic derives from the two tone interval between the first and third notes, which is known as a major third. The major scale derives from the Ionian mode and was in use long before it was widely adopted by serious composers. It was condemned by the medieval church as too lustful and found only in folk and traditional music at that time. The establishment of the laws of harmony in the sixteenth century, however, made it the fundamental building block of all western music.