Modern classical music depends almost entirely on the major and minor scales with rare experiments in the Phrygian mode. But in the early twentieth century, composers began to experiment with atonality, defined, according to Wikipedia, as “music that lacks a tonal center, or key.” Atonality, in this sense, usually describes a composition method in which a hierarchy of harmonies focusing on a single, central triad is not used, and the notes of the chromatic scale function independently of one another. Most famous among atonal composers are those of the “Second Viennese School,” principally Alban Berg, Arnold Schönberg, and Anton Webern.
These composers depended on “twelve-tone technique”—also known as dodecaphony and twelve-tone serialism. They constructed “tone rows” in which the twelve tones of an octave were laid out in an order that was then used as the basis for composing a piece.
Few composers joined the original three of the Second Viennese School, and atonality has largely faded from the musical composition scene. Today tonality, the use of the major and minor keys, is again dominant. But music written in the modes continues to haunt me.
These days, when I want to comfort myself, I sit at my magnificent Steinway grand and play my own arrangement of “Greensleeves” in the Dorian mode. It takes me back to a different time and at the same time grounds me in present.
Tom Glenn, Writer 