a musical form for soloist (or soloists) and orchestra, usually consisting of three movements (fast-slow-fast). The term is derived from the Latin verb "concertare", which means a fight or a dispute between rivals.
In the classical period, most of the first movements of a concerto were based on the sonata-form, with its three main sections (Exposition - Development - Recapitulation), usually two contrasted themes in the first section, a cadenza near the end of the movement, and a coda at its conclusion.
The second movement can be based, again, on a shortened sonata-form, on a theme with variations, or on free form. Third movements are usually written in rondo form, but can also be in the sonata form.
The concerto is one of the most important opportunities for the soloist to display his technical and expressive virtuosity. Some of the greatest concertos were written by composers such as Haydn, Boccherini, Viotti, Mozart, Beethoven, Paganini, Berlioz, Mendelssohn, Schumann, Brahms, and Liszt .
