Opera is a form of theatre in which music has a leading role and the parts are taken by singers, but is distinct from musical theater. Such a 'work' (the literal translation of Italian word 'opera') is typically a collaboration between a composer and a librettist and incorporates a number of the performing arts, such as acting, scenery, costume, and sometimes dance or ballet. The performance is typically given in an opera house, accompanied by an orchestra or smaller musical ensemble, which since the early 19th century has been led by a conductor. Opera is a key part of the Western classical music tradition. Originally understood as an entirely sung piece, in contrast to a play with songs, opera has come to include numerous genres, including some that include spoken dialogue such as musical theater, Singspiel and Opéra comique. In traditional number opera, singers employ two styles of singing: recitative, a speech-inflected style, and self-contained arias. The 19th century saw the rise of the continuous music drama. Opera originated in Italy at the end of the 16th century (with Jacopo Peri's mostly lost Dafne, produced in Florence in 1598) and soon spread through the rest of Europe: Heinrich Schütz in Germany, Jean-Baptiste Lully in France, and Henry Purcell in England all helped to establish their national traditions in the 17th century. In the 18th century, Italian opera continued to dominate most of Europe (except France), attracting foreign composers such as George Frideric Handel. Opera seria was the most prestigious form of Italian opera, until Christoph Willibald Gluck reacted against its artificiality with his 'reform' operas in the 1760s. The most renowned figure of late 18th-century opera is Wolfgang Amadeus Mozart, who began with opera seria but is most famous for his Italian comic operas, especially The Marriage of Figaro (Le nozze di Figaro), Don Giovanni, and Così fan tutte, as well as Die Entführung aus dem Serail (The Abduction from the Seraglio), and The Magic Flute (Die Zauberflöte), landmarks in the German tradition. The first third of the 19th century saw the high point of the bel canto style, with Gioachino Rossini, Gaetano Donizetti and Vincenzo Bellini all creating works that are still performed. It also saw the advent of Grand Opera typified by the works of Auber and Meyerbeer. The mid-to-late 19th century was a golden age of opera, led and dominated by Giuseppe Verdi in Italy and Richard Wagner in Germany. The popularity of opera continued through the verismo era in Italy and contemporary French opera through to Giacomo Puccini and Richard Strauss in the early 20th century. During the 19th century, parallel operatic traditions emerged in central and eastern Europe, particularly in Russia and Bohemia. The 20th century saw many experiments with modern styles, such as atonality and serialism (Arnold Schoenberg and Alban Berg), Neoclassicism (Igor Stravinsky), and Minimalism (Philip Glass and John Adams). With the rise of recording technology, singers such as Enrico Caruso and Maria Callas became known to much wider audiences that went beyond the circle of opera fans. Since the invention of radio and television, operas were also performed on (and written for) these mediums. Beginning in 2006, a number of major opera houses began to present live high-definition video transmissions of their performances in cinemas all over the world. Since 2009, complete performances can be downloaded and are live streamed. 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 Lorenzo Da Ponte. Traditional opera, often referred to as 'number opera', consists of two modes of singing: recitative, the plot-driving passages sung in a style designed to imitate and emphasize the inflections of speech, and aria (an 'air' or formal song) in which the characters express their emotions in a more structured melodic style. Vocal duets, trios and other ensembles often occur, and choruses are used to comment on the action. In some forms of opera, such as singspiel, opéra comique, operetta, and semi-opera, the recitative is mostly replaced by spoken dialogue. Melodic or semi-melodic passages occurring in the midst of, or instead of, recitative, are also referred to as arioso. The terminology of the various kinds of operatic voices is described in detail below. During both the Baroque and Classical periods, recitative could appear in two basic forms, each of which was accompanied by a different instrumental ensemble: secco (dry) recitative, sung with a free rhythm dictated by the accent of the words, accompanied only by basso continuo, which was usually a harpsichord and a cello; or accompagnato (also known as strumentato) in which the orchestra provided accompaniment. Over the 18th century, arias were increasingly accompanied by the orchestra. By the 19th century, accompagnato had gained the upper hand, the orchestra played a much bigger role, and Wagner revolutionized opera by abolishing almost all distinction between aria and recitative in his quest for what Wagner termed 'endless melody'. Subsequent composers have tended to follow Wagner's example, though some, such as Stravinsky in his The Rake's Progress have bucked the trend. The changing role of the orchestra in opera is described in more detail below. 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 opera, a singular noun meaning 'work' and also the plural of the noun opus. According to the Oxford English Dictionary, the Italian word was first used in the sense 'composition in which poetry, dance, and music are combined' in 1639; the first recorded English usage in this sense dates to 1648. Dafne by Jacopo Peri was the earliest composition considered opera, as understood today. It was written around 1597, largely under the inspiration of an elite circle of literate Florentine humanists who gathered as the 'Camerata de' Bardi'. Significantly, Dafne was an attempt to revive the classical Greek drama, part of the wider revival of antiquity characteristic of the Renaissance. The members of the Camerata considered that the 'chorus' parts of Greek dramas were originally sung, and possibly even the entire text of all roles; opera was thus conceived as a way of 'restoring' this situation. Dafne, however, is lost. A later work by Peri, Euridice, dating from 1600, is the first opera score to have survived to the present day. The honour of being the first opera still to be regularly performed, however, goes to Claudio Monteverdi's L'Orfeo, composed for the court of Mantua in 1607. The Mantua court of the Gonzagas, employers of Monteverdi, played a significant role in the origin of opera employing not only court singers of the concerto delle donne (till 1598), but also one of the first actual 'opera singers'; Madama Europa. Opera did not remain confined to court audiences for long. In 1637, the idea of a 'season' (Carnival) of publicly attended operas supported by ticket sales emerged in Venice. Monteverdi had moved to the city from Mantua and composed his last operas, Il ritorno d'Ulisse in patria and L'incoronazione di Poppea, for the Venetian theatre in the 1640s. His most important follower Francesco Cavalli helped spread opera throughout Italy. In these early Baroque operas, broad comedy was blended with tragic elements in a mix that jarred some educated sensibilities, sparking the first of opera's many reform movements, sponsored by the Arcadian Academy, which came to be associated with the poet Metastasio, whose libretti helped crystallize the genre of opera seria, which became the leading form of Italian opera until the end of the 18th century. Once the Metastasian ideal had been firmly established, comedy in Baroque-era opera was reserved for what came to be called opera buffa.Before such elements were forced out of opera seria, many libretti had featured a separately unfolding comic plot as sort of an 'opera-within-an-opera.' One reason for this was an attempt to attract members of the growing merchant class, newly wealthy, but still not as cultured as the nobility, to the public opera houses. These separate plots were almost immediately resurrected in a separately developing tradition that partly derived from the commedia dell'arte, a long-flourishing improvisatory stage tradition of Italy. Just as intermedi had once been performed in between the acts of stage plays, operas in the new comic genre of 'intermezzi', which developed largely in Naples in the 1710s and '20s, were initially staged during the intermissions of opera seria. They became so popular, however, that they were soon being offered as separate productions.