The main schools of music in the 20th century can be roughly divided into: this kind of music is an art school that rose in Germany and Austria at the beginning of the 20th century before the First World War. As the antonym of impressionism, it appeared in the field of painting and poetry in Germany, represented by Kandinsky, and then extended to the field of music. There are certain social reasons for its appearance: at that time, Germany was under authoritarian rule, and social contradictions were prominent and turbulent, which led to the expression of some artists and their subjective feelings; They think that the world is full of suffering, ugliness and terror, so they express their subjective feelings with exaggerated and distorted abstract geometric figures. 1 9 1 8, Austrian composer Thyssen used expressionism to comment on music works, from which expressionism style appeared and gradually became popular in the music field. Expressionist music has the characteristics of anti-tradition, incoherent melody, irregular beat, extreme dynamic change, unclear structure, sharp and discordant chord sounds, and the most important thing is to use the phonology of 1 2. Therefore, the lyricism of romanticism, the logic of classicism and the color beauty of impressionism can't be found in expressionist music, which is very strange. Expressionist music abandons the description of the surrounding world, emphasizes the expression of inner experience, directly pursues deep feelings, and advocates that music should express people's ideological essence and inner soul.

Main representative: Schoenberg, Austrian composer and music theorist. He and his two students, Berger and Wei Boen, are both representative composers of 1 2 music, and they became the "New Vienna Music School". Schoenberg's masterpieces include Pietro on the Moon, Survivor of Warsaw and Variations for a Band. Also known as "new baroque music", it is one of the popular schools of modern music during the two world wars in the 1920s. Aesthetically, neoclassical music pursues balanced, stable and rational music, opposes the inflated subjective consciousness in post-romantic music and expresses strong personal feelings. Oppose heteronomy, support self-discipline, put forward the idea of returning to Bach, adopt the absolute music form of "music is music", pay more attention to the technology and form of music, rather than the content, and replace emotional expression with music form. Specifically, it pursues the balance and symmetry of melody and rhythm. Advocate a fresh and standardized music structure and oppose a free and loose structure; Advocate pure music, revive the genre form before romanticism, and oppose title music; Advocate miniaturization and indoor band preparation, and oppose huge band preparation. However, this school often combines the musical forms of Bach and other composers with the new musical language of the 20th century, and tends to adopt the method of extended tonality or even atonality, with complex harmony, often adding novel and discordant sounds of the 20th century, sharp, novel and discordant sounds peculiar to the orchestration, and changeable musical instrument timbre, so it has not returned to the functional tonality system of the classical period, nor has it really reflected the true colors of the music of the Baroque period.

Therefore, people call this school of retro music "neoclassical music" to distinguish it from the classical period. The representative figure of neoclassical music school: Stravinsky; Russian-American composer, representing composers Firebird, Sacrifice to Spring and Puccinia. Compared with the nationalist music in the19th century, the depth of neo-nationalist music in the 20th century in eulogizing the national content and people's life has been weakened, and composers pay attention to the connotation of folk music itself and the new discovery of its characteristics. In the processing of music materials, neo-nationalist music emphasizes the absorption of people's inherent characteristics and melodies, and creates according to folk modes, scales and rhythms. In the absorption of musical features, this kind of music is more or less influenced by some new composing techniques. The representative figure of this music genre: Bartok; Hungarian composer, whose representative works include piano textbooks such as Small Universe and Dedicated to Children. Opera "The Castle of Duke Bluebeard" and so on.

In addition to the above four kinds, music in the 20th century also appeared: differential music, noise music, sequence music, occasional music, electronic music and other musical forms. Since 1970s, the development of music in the 20th century has shown a diversified trend. No style occupies a central position. Composers pay attention to the creation and discovery of new techniques, new acoustics and new tricks, and make more use of the new expression techniques accumulated in the past decades to combine with traditional music to create. Romantic trend of thought is gradually returning, and atonal music is quietly withdrawing from the music trend.