A 12-tone composition

A 12-tone composition is a method of composition that uses all twelve notes of the chromatic scale in a specific order, without repeating any notes until all twelve have been played. This technique was developed by Austrian composer Arnold Schoenberg in the early 20th century as a way to create music that didn't rely on traditional tonal relationships.

In a 12-tone composition, the composer creates a "tone row" or series of all twelve pitches in a specific order, and then uses that row as the basis for the rest of the piece. The row can be transposed, inverted, reversed, and otherwise manipulated in various ways to create motifs and themes throughout the composition.

Some famous examples of 12-tone compositions include Schoenberg's "Pierrot Lunaire" and Alban Berg's "Violin Concerto." This technique has been used by many composers since its inception and continues to be a popular method of composition in contemporary classical music.