The words of an opera are known as the libretto (literally "small book"). Some composers, notably Wagner, have written their own libretti; others have worked in close collaboration with their librettists, e.g. Mozart with

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Origins
The Italian word opera means "work", both in the sense of the labour done and the result produced. The Italian word derives from the Latin word opera, a singular noun meaning "work" and also the plural of the noun opus.

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Operatic vocal technique evolved, in a time before electronic amplification, to allow singers to produce enough volume to be heard over an orchestra, without the instrumentalists having to substantially compromise their volume.
Vocal classifications

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Before the 1700s, Italian operas used a small string orchestra, but it rarely played to accompany the singers. Opera solos during this period were

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Since the days of Handel and Mozart, many composers have favored Italian as the language for the libretto of their operas. From the Bel Canto era to Verdi, composers would

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Outside the US, and especially in Europe, most opera houses receive public subsidies from taxpayers. In Milan, Italy, 60% of La Scala's annual

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A milestone for opera broadcasting in the U.S. was achieved on 24 December 1951, with the live broadcast of Amahl and the Night Visitors,

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