Dress rehearsal

A rehearsal is an activity in the performing arts that occurs as preparation for a performance in music, theatre, dance and related arts, such as opera, musical theatre and film production. It is undertaken as a form of practising, to ensure that all details of the subsequent performance are adequately prepared and coordinated. The term "rehearsal" typically refers to ensemble activities undertaken by a group of people. For example, when a musician is preparing a piano concerto alone in their music studio, this is called "practicing", but when they begin to practice the concerto with an orchestra, this activity is called a "rehearsal". The music rehearsal takes place in a music rehearsal space.

A rehearsal may involve as few as two people, as with a small play for two actors, an art song performance by a singer and a pianist or a folk music duo of a singer and a guitar player. On the other end of the spectrum, a rehearsal can be held for a very large orchestra with over 100 performers and a choir. A rehearsal can involve only performers of one type, as in an a cappella choir show, in which a group of singers perform without instrumental accompaniment or a play involving only theatre actors; it can involve performers of different instruments, as with an orchestra, rock band or jazz "big band"; vocal and instrumental performers, as with opera and choral works accompanied by orchestra; or a mix of actors, vocalists, instrumentalists and dancers, as with musical theatre.

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