A tone row is a specific sequence of the twelve different pitches in the chromatic scale, used primarily in twelve-tone music. This method, developed by composer Arnold Schoenberg, allows composers to create music without a tonal center, ensuring that all notes are treated equally. The tone row can be manipulated through various techniques, such as inversion, retrograde, and transposition, providing a framework for composition. In a tone row, each pitch is represented only once before any note is repeated, creating a unique melodic and harmonic structure. This approach contrasts with traditional tonal music, where certain notes are emphasized, leading to a sense of hierarchy and resolution.