opera, a staged drama set to music in its entirety, made up of vocal pieces with instrumental accompaniment and usually with orchestral overtures and interludes. In some operas the music is continuous throughout an act; in others it is broken up into discrete pieces, or “numbers,” separated either by recitative (a dramatic type of singing that approaches speech) or by spoken dialogue. This article focuses on opera in the Western tradition. For an overview of opera and operalike traditions in Asia (particularly in China), see the appropriate sections of Chinese music, Japanese music, South Asian arts, and Southeast Asian arts; see also short entries on specific forms of Chinese opera, such as chuanqi, jingxi, kunqu, and nanxi.

The English word opera is an abbreviation of the Italian phrase opera in musica (“work in music”). It denotes a theatrical work consisting of a dramatic text, or libretto (“booklet”), that has been set to music and staged with scenery, costumes, and movement. Aside from solo, ensemble, and choral singers onstage and a group of instrumentalists playing offstage, the performers of opera since its inception have often included dancers. A complex, often costly variety of musico-dramatic entertainment, opera has attracted both supporters and detractors throughout its history and has sometimes been the target of intense criticism. Its detractors have viewed it as an artificial and irrational art form that defies dramatic verisimilitude. Supporters have seen it as more than the sum of its parts, with the music supporting and intensifying the lyrics and action to create a genre of greater emotional impact than either music or drama could achieve on its own. In his 1986 autobiography, stage and film director Franco Zeffirelli warned against taking opera too literally:

Short men in armour and large ladies in chiffon singing about ancient Egypt don’t make much sense at one level [but] they can…reveal to us the confusions of emotion and loyalty, the nature of power and pity, that could not be so movingly expressed in any other way.

The preparation of an opera performance involves the work of many individuals whose total contributions sometimes spread across a century or more. The first, often unintentional, recruit is likely the writer of the original story. Then comes the librettist, who puts the story or play into a form—usually involving poetic verse—that is suitable for musical setting and singing. The composer then sets that libretto to music. Architects and acousticians will have designed an opera house suited or adaptable to performances that demand a sizable stage; a large backstage area to house the scenery; a “pit,” or space (often below the level of the stage) to accommodate an orchestra; and seating for a reasonably large audience. A producer (or director) has to specify the work of designers, scene painters, costumers, and lighting experts. The producer, conductor, and musical staff must work for long periods with the chorus, dancers, orchestra, and extras as well as the principal singers to prepare the performance—work that may last anywhere from a few days to many months. All of this activity, moreover, takes place in conjunction with the work not only of researchers and editors who painstakingly prepare the musical score, especially in the case of revivals of works long forgotten or published long ago, but also of the theatre’s administrative staff, which includes the impresario and others responsible for bookings, ticket sales, and other business matters.

One of the most variable facets of opera during its long history has been the balance struck between music and poetry or text. The collaborators of the first operas (in the early 17th century) believed they were creating a new genre in which music and poetry, in order to serve the drama, were fused into an inseparable whole, a language that was in a class of its own—midway between speaking and singing. In the decades and centuries that followed, the balance between these elements repeatedly shifted to favour the music at the expense of the text and the integrity of the drama, only to be brought back into relative equilibrium by various “reforms.” More than one desirable balance between music, text, and drama is possible, however, and over time the aesthetic ideals of opera and its creators have successfully adapted to the changing tastes and attitudes of patrons and audiences, while also accommodating linguistic diversity and assorted national preferences. As a result, opera has endured in Western culture for more than 400 years.

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Moreover, since the late 20th century, new ways of delivering opera to the public—on video and DVD, in cinematography, or via high-definition simulcast in movie theatres—have increasingly made the genre more accessible to a larger audience, and such novelties will inevitably change public attitudes and appreciation of the art form. It remains to be seen, however, how these media might also change the way in which composers, librettists, impresarios, and performers approach opera, and whether the genre’s musical and theatrical values will consequently be altered in fundamental ways.

The early history

Music historians have continued to debate opera’s ancestry. The plays of the ancient Greek dramatists Aeschylus, Sophocles, and Euripides combined poetic drama and music. During the Middle Ages, biblical dramas that were chanted or interspersed with music were known under various labels, including liturgical dramas (ordines) and similar plays performed in church. These and related musico-dramatic forms may have become indirect ancestors of opera, but the earliest universally accepted direct ancestors of opera appeared in 16th-century Italy.

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