Chromaticism refers to the use of notes outside the standard scale of a piece of music, often incorporating all twelve pitches available in Western music. This technique adds color and complexity to melodies and harmonies, allowing composers to create richer emotional expressions. In contrast to diatonic music, which sticks to a specific scale, chromaticism introduces variations that can enhance tension and resolution. It is commonly found in the works of composers like Richard Wagner and Frédéric Chopin, who utilized chromatic notes to evoke deeper feelings and create more intricate musical landscapes.