Symphony is a part of the western classical music. It is an extended form of musical composition and is scored using orchestra. Of course symphony does not imply any specific form. While most of these symphonies are composed using the sonata principle, many of them are also tonal works in four movements using the first in sonata forms.

Sonata form is described by the experts as the structure of "classical" symphony. Deviations are there. Great and legendary symphony composers like Wolfgang Amadeus Mozart, Joseph Haydn, and Ludwig van Beethoven composed symphonies that did not conform to this particular model.

As a terminology the word "symphony" has Greek origin. Basically it refers to "agreements or concords of sound" or the concert of vocal and instrumental music. Such music is harmonious in nature and that is why they are called symphonies

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In Latin form the word Symphonia described various instruments that is capable of producing multiple sounds simultaneously. Different meanings were assigned to the term in France and England . Dulcimer in England , hurdy gurdy in France , and spinters and virginals in Germany , all referred to the term symphony.

Gradually the term got wider uses wit composers of the 16 th and 17 th century composers like Giovanni Gabrieli, Adriano Banchieri, Lodovico Grossi da Viadana, and Heinrich Schutz and such other legendary composers.

During the 17 th century which refers to the Baroque period, symphony referred to a wide range of compositions. It included operas, sonatas, as well as concertos. During those days the terms overture, sinfonia, and symphony were used interchangeably.

Relatively less explored form of symphony was the ripieno concerto that resembles concerts that are made with strings and continuo. However, it does not contain any solo instrument. Early symphonies have three movements inherent to it; quick-slow-quick. In the 18 th century it had four constituents; namely, opening sonata, slow movement, minuet with trio, and an allegro.

With Beethoven, romanticism took symphony to an altogether new level. Long large scale symphonies were introduced in the twentieth century. However, even in the twenty first century, symphony has not shelved its characteristic of using orchestra.