A symphony is an extended musical form written for an orchestra. Traditional symphonies contain four movements, at least one of which uses [sonata form](https://www.masterclass.com/articles/sonata-form-in-music). In most cases, a symphony consists of instrumental music, though vocal choruses feature prominently in some symphonies, including Ludwig van Beethoven's *Symphony No. 9* and Gustav Mahler's *Symphony No. 2*. Symphonies are popular among musicians and audiences alike, and symphonies are often the main event of classical music concerts worldwide.\nThe symphony is a medium for compositional innovation, so the format of symphonies varies greatly throughout history:\n\n- __Baroque__: The modern symphony can trace its roots to the Baroque tradition of an Italian overture, also known as an opera sinfonia. Composer Alessandro Scarlatti popularized overtures as instrumental introductions to vocal operas, and these overtures live on in both classical music and musical theatre. \n- __Classical__: The Classical era ushered in a more formal symphony. Tomaso Albinoni structured his 1735 *Sinfonia in D Major* using sonata form, inspiring generations of instrumental composers. Matthias Georg Monn charted the movement known as the [Viennese School](https://www.masterclass.com/articles/first-viennese-school-timeline), which greatly influenced the three most prominent symphonists of the Classical era: Wolfgang Amadeus Mozart, Franz Joseph Haydn, and Ludwig van Beethoven. Other Classical symphonists include J.C. Bach, C.P.E. Bach, and Giovanni Battista Sammartini.\n- __Romantic__: In the Romantic era of the nineteenth century, symphonies became vessels for emotion and drama. Composers like Beethoven, Hector Berlioz, Johannes Brahms, Felix Mendelssohn, and Piotr Ilyich Tchaikovsky imbued their works with drama and even storytelling. In some cases, like Berlioz's *Symphonie Fantastique*, the music is programmatic, with symphony instruments portraying characters and story points.\n- __Twentieth and twenty-first centuries__: Modern composers do not adhere to the Classical- and Romantic-era structure of four movements and sonata form. Modern and postmodern symphonies range from one movement to more than 20, and they may last for a matter of minutes or more than an hour.\n\nOver the centuries, the characteristics of a symphony have evolved, but certain defining points remain consistent:\n\n1. __Large ensemble__: In the overwhelming majority of cases, symphonies feature orchestral instruments like violin, viola, cello, contrabass, trumpet, trombone, horn, flute, clarinet, oboe, and various percussion. Contemporary symphonies may feature less standard instruments, such as keyboards and electric guitars.\n2. __Long-form__: Some symphonies are a few minutes in length, but most exceed 20 minutes. Mahler's *Symphony No. 3*, though, is an example of a symphony that can take more than an hour to perform.\n3. __Multiple movements__: Nearly all symphonies use multiple movements with various tempos, keys, and tonalities. The Classical symphony form typically begins with an allegro rondo or sonata in [4/4 time](https://www.masterclass.com/articles/guide-to-time-signatures-in-music), with a slow second movement, a 3/4 minuet third movement, and another allegro rondo or sonata as its fourth movement. More contemporary symphonies are less structured.\nThere are many notable symphonies composed throughout the history of music:\n\n1. *Symphony, Wotquenne 177, Helm 653 in E minor* (1756) by Carl Philipp Emanuel Bach \n2. *Symphony No. 40 in G minor, K. 550* (1788) by Wolfgang Amadeus Mozart \n3. *Symphony No. 5 in C minor* (1808) by Ludwig van Beethoven \n4. *Symphony No. 3 in A minor "Scottish Symphony"* (1842) by Felix Mendelssohn\n5. *Symphony No. 6 in B minor "Pathetique"* (1893) by Piotr Ilyich Tchaikovsky \n6. *Symphony in C* (1940) by Igor Stravinsky\n7. *Symphony No. 3* (1995) by Krzysztof Penderecki \nBecome a better musician with the [MasterClass Annual Membership](https://www.masterclass.com). Gain access to exclusive video lessons taught by the world’s best, including Itzhak Perlman, St. Vincent, Sheila E., Timbaland, Herbie Hancock, Tom Morello, and more.\n\nFor centuries, the symphony has been an iconic musical form played by classical orchestras.