Twelve-tone music, also called dodecaphony, was Arnold Schoenberg’s technique of organizing a work, movement, or passage around a fixed set of twelve non-repeating notes. The composer bases his or her melodic material on the intervallic relationships of the set or some subset, although the set itself need not appear as a melody. The set is also called a row, tone row, or series. One can also apply contrapuntal techniques of retrograde, inversion, and retrograde inversion – running the notes backward, inverting the intervals, or doing both at once. Twelve-tone writing is not necessarily the same thing as atonality; one can arrange the row in a way that the resulting music sounds tonal.