20th Century Classical Period At the turn of the 20th century classical music was characteristically late Romantic in style, while at the same time the Impressionist movement, spearheaded by Claude Debussy was taking form. America began forming its own vernacular style of classical music, notably in the works of Charles Ives, John Alden Carpenter, and George Gershwin, while in Vienna, Arnold Schoenberg conceived atonality, and later developed the twelve-tone technique. Classical music in the 20th century varied greatly, from the expressionism of early Schoenberg, Neoclassical music of Igor Stravinsky, the futurism of Luigi Russolo, Alexander Mossolov, early Prokofiev and Antheil, to the microtonal music of Julián Carrillo, Alois Hába, Harry Partch, and Ben Johnston, to the socialist realism of late Prokofiev and Glière, Kabalevsky, and other Russian composers, as well as the simple harmonies and rhythms of minimalist composers such as Steve Reich, and Philip Glass, to the musique concrète of Pierre Schaeffer and the intuitive music of Karlheinz Stockhausen; from the total serialism of Pierre Boulez and the political commitment of Luigi Nono to the aleatoric music of John Cage. Perhaps the most salient feature during this time period of classical music was the increased use of dissonance. Because of this, the twentieth century is sometimes called the "Dissonant Period" of classical music, following the common practice period, which emphasized consonance. The watershed transitional moment was the international Paris Exposition celebrating the centennial of the French Revolution, in 1889. Composers such as Anton Webern, Elliott Carter, Edgard Varèse, Milton Babbitt, Luigi Nono and Luciano Berio have devoted followings within the avant-garde, but are often attacked outside of it. As time has passed, however, it is increasingly accepted, though by no means universally so, that the boundaries are more porous than the many polemics would lead one to believe: many of the techniques pioneered by the above composers show up in popular music by The Beatles, Deep Purple, Yes, Genesis, King Crimson, Pink Floyd, ELP, Mike Oldfield, Enigma, Vangelis, Jean Michel Jarre, in film scores and video game music that draw mass audiences. It should be kept in mind that this article presents an overview of twentieth-century classical music and many of the composers listed under the following trends and movements may not identify exclusively as such and may be considered as participating in different movements. For instance, at different times during his career, Igor Stravinsky may be considered a romantic, modernist, neoclassicist, and a serialist. Romantic style Particularly in the early part of the century, many composers wrote music which was an extension of nineteenth-century Romantic music, and traditional instrumental groupings such as the orchestra and string quartet remained the most usual. Traditional forms such as the symphony and concerto remained in use. While some writers hold that Debussy's Prélude à l'après-midi- d'un faune and Schoenberg's Verklärte Nacht are dramatic departures from Romanticism and have strong modernist traits, others hold that the Schoenberg work is squarely within the late-Romantic tradition of Wagner and Brahms and, more generally, that "the composer who most directly and completely connects late Wagner and the twentieth century is Arnold Schoenberg". Many prominent composers — among them Sergei Prokofiev, Dmitri Shostakovich, Maurice Ravel, and Benjamin Britten — made significant advances in style and technique while still employing a melodic, harmonic, rhythmic, structural, and textural language which was related to that of the nineteenth century. Music along these lines was written throughout the twentieth century, and continues to be written today. Impressionism Impressionism was a French revolt, led by Claude Debussy, against the emotional exuberance and epic themes of German Romanticism exemplified by Wagner. In Debussy's view, art was a sensuous experience, rather than an intellectual or ethical one. He urged his countrymen to rediscover the French masters of the eighteenth century, for whom music was meant to charm, to entertain, and to serve as a "fantasy of the senses". Other composers associated with impressionism include Maurice Ravel, Albert Roussel, Isaac Albéniz, Paul Dukas, Manuel de Falla, Charles Martin Loeffler, Charles Griffes, Frederick Delius, Ottorino Respighi, and Karol Szymanowski. Although impressionism is generally held to have been superseded in the 1920s by neoclassicism, many French composers continued its language, including Albert Roussel, Charles Koechlin, André Caplet, and, later, Olivier Messiaen. Composers from non-Western cultures, such as Tōru Takemitsu, and jazz musicians such as Duke Ellington, Gil Evans, Art Tatum, and Cecil Taylor, also have been strongly influenced by the impressionist musical language. Expressionism Expressionism was a prominent artistic trend associated especially with Austria and Germany before, during, and immediately after World War I. In some measure a reaction against the perceived passive nature of impressionism, it emphasized an eruptive immediacy of expressive feeling, often based on the psychology of the unconscious. Expressionism is primarily identified with Arnold Schoenberg’s "free atonal’ period" (1908–1921), in particular the monodrama Erwartung, the Klavierstück op. 11, no. 3, and the first and last of his Five Orchestral Pieces op. 16. Certain works from this same period by his pupils Alban Berg and Anton Webern are also usually included. Although this music sets out from Wagner’s chromatic harmony (especially Kundry’s music in Parsifal), it tends to avoid cadence, repetition, sequence, balanced phrases, and any reference to traditional forms or procedures, for which reason it came to be associated with a rejection of tradition. Other composers active in approximately this period such as Gustav Mahler, Alexander Skryabin, Josef Matthias Hauer, Igor Stravinsky, Karol Szymanowski, Béla Bartók, Paul Hindemith, Charles Ives, and Ernst Krenek also exhibit expressionist traits, while important stage works of the 1920s by Kurt Weill, Hindemith, and Krenek retain expressionistic textual and visual aspects even though their musical language no longer reflects expressionism's aesthetic principles. By the late 1920s, though many composers continued to write in a vaguely expressionist manner, it was being supplanted by the more impersonal style of the German Neue Sachlichkeit and neoclassicism. Because expressionism, like any movement that had been stigmatized by the Nazis, gained a sympathetic reconsideration following World War II, expressionist music resurfaced in works by composers such as Hans Werner Henze, Pierre Boulez, Peter Maxwell Davies, Wolfgang Rihm, and Bernd Alois Zimmermann. Futurism Futurism was an initially Italian artistic movement founded in 1909 by Filippo Tommaso Marinetti, and soon embraced by the Russian avant garde. In 1913, the painter Luigi Russolo published a manifesto, L'arte dei rumori (The Art of Noises), calling for the incorporation of noises of every kind into music. In addition to Russolo, composers directly associated with this movement include the Italians Silvio Mix, Nuccio Fiorda, Franco Casavola, and Pannigi (whose 1922 Ballo meccanico included two motorcycles), and the Russians Artur Lourié, Mikhail Matyushin, and Nikolai Roslavets. Though few of the futurist works of these composers are performed today, the influence of futurism on the later development of twentieth-century music was enormous. Sergei Prokofiev, Maurice Ravel, Igor Stravinsky, Arthur Honegger, George Antheil, Leo Ornstein, and Edgard Varèse are among the notable composers in the first half of the century who were influenced by futurism. Characteristic features of later twentieth-century music with origins in futurism include the prepared piano, integral serialism, extended vocal techniques, graphic notation, improvisation, and minimalism. Second Viennese School, atonality, twelve-tone technique, and serialism Arnold Schoenberg is one of the most significant figures in 20th century music. In 1921, he developed the twelve-tone technique of composition, which he first described privately to his associates in 1923. In Europe, the "punctual", "pointist", or "pointillist" style of Messiaen's "Mode de valeurs et d'intensités"—in which individual tones' characteristics, or "parameters" are each determined independently—was very influential in the years immediately following 1951 among composers such as Pierre Boulez, Karel Goeyvaerts, Luigi Nono and Karlheinz Stockhausen. Free dissonance and experimentalism In the early part of the 20th century Charles Ives integrated American and European traditions as well as vernacular and church styles, while innovating in rhythm, harmony, and form. Edgard Varèse wrote highly dissonant pieces that utilized unusual sonorities and futuristic, scientific sounding names. Neoclassicism Electronic music Technological advances in the twentieth century enabled composers to use electronic means of producing sound. After the Second World War, magnetic tape became available for the creation of music by recording sounds and then manipulating them in some way. When the source material was acoustical sounds from the everyday world, the term musique concrète was used; when the sounds were produced by electronic generators, it was designated electronic music. After the 1950s, the term "electronic music" came to be used