A symphony is a specific form of musical composition that many composers use when writing music. These pieces are usually large in scale, written for a large orchestra, and are made up of four individual movements. A movement is a single piece of music, like a song on a rock album, and a symphony would have four larger “songs,” or movements. The four movements of a symphony are usually structured as follows:

• First Movement: This is usually in a form called Sonata form and is often the most significant of the four movements.

• Second Movement: This is usually slow and lyrical.

• Third Movement: This is usually a dance, or sometimes a “Scherzo,” which is a light, quick piece.

• Fourth Movement: This is almost always fast and exciting and is referred to as the finale.

The symphony grew out of earlier forms and was formalized by the composer Joseph Haydn in the 1700s. Later composers like Beethoven, Brahms, Tchaikovsky, and Mahler expanded what they could be. The word symphony is derived from the Greek word symphōnía, meaning "agreement or concord of sound". Today, it refers to a specific group of musicians, such as a “symphony orchestra,” or the musical form, such as “Beethoven’s 5th symphony”.

Symphonies are almost always scored for an orchestra consisting of a string section (violin, viola, cello, and double bass), brass, woodwind, and percussion instruments which altogether number about 30 to 100 musicians. They are notated in a musical score, which contains all the instrument parts. Since most orchestra concerts will have a symphony as their headline piece, they are usually the longest piece on a concert, but they can vary wildly in size, length, and complexity.