Symphony is a large-scale orchestral genre established in the second half of18th century. The word "symphony" comes from the Greek word "symphony", which originally means "the sounds sound together". It is a form of orchestral suite based on the principle of sonata. The predecessor of symphony is Italian opera overture (sinfonia) in Baroque period. /kloc-In the first half of the 8th century, composers used the fast-slow-fast structure of Italian opera overture to create orchestral works, which were called symphonies. Since then, symphonies have gradually replaced baroque band concertos and become the main instrumental music form in concerts. In the period of classicism, the true establishment and development of symphony was mainly attributed to the music schools in Mannheim, Berlin and Vienna. The Mannheim School laid the basic structure of the four movements of the classical symphony, and formed the symphonic suite form of Allegro-Andante-minuet-Allegro finale. /kloc-In the second half of the 8th century, Haydn of Vienna Classical School reformed, developed and perfected this symphony form, and later Beethoven pushed the symphony to the peak of development. Symphony has extensive artistic generalization and profound philosophy in music performance. Like a sonata, its structure is usually four movements. The Romantic Period's symphonies have developed to a certain extent, which are characterized by freer literary titles and musical structures, an indefinite number of movements (symphonies composed of one, two, five, six and seven movements), a huge orchestra, gorgeous and full acoustics and rich national style. Represented by the works of Schubert, Berlioz, Liszt, Brahms, dvorak, Pyotr Il'yich Tchaikovsky, brukner, Mahler and other composers. At the climax of its development, a large number of musicians were concentrated around Vienna, with Strauss and Strauss as the masters. Therefore, the annual symphony New Year concert in Vienna is usually limited to Strauss and Strauss. Symphony in the 20th century was influenced by various musical trends of thought, with unique conception, large and small band organization, complicated acoustics and diverse styles. Represented by the works of composers such as Debussy, Copeland, Mei Xian, Oneig, hindemith and Pistons.