Opera seria in the context of "Opernhaus am Zwinger"

A number opera (Italian: opera a numeri; German: Nummeroper; French: opéra à numéros) is an opera consisting of individual pieces of music ('numbers') which can be easily extracted from the larger work. They may be numbered consecutively in the score, and may be interspersed with recitative or spoken dialogue. Opera numbers may be arias, but also ensemble pieces, such as duets, trios, quartets, quintets, sextets or choruses. They may also be ballets and instrumental pieces, such as marches, sinfonias, or intermezzi. The number opera format was standard until the mid-19th century and most opera genres, including opera seria, opera buffa, opéra comique, ballad opera, Singspiel, and grand opera, were constructed in this fashion.

The replacement of numbers with more continuous music began in operas by Jommelli, Traetta, Gluck, and especially Mozart, whose late operas Le Nozze di Figaro and Don Giovanni contain several segments in which different numbers are unified by bridge passages to form a musical whole. This trend became even more striking in the operas of the German composers Beethoven, Weber, and Meyerbeer, while their Italian and French contemporaries Rossini, Donizetti, Bellini, and Auber retained the number opera style.

Comic opera, sometimes known as light opera, is a sung dramatic work of a light or comic nature, usually with a happy ending and often including spoken dialogue.

Forms of comic opera first developed in late 17th-century Italy. By the 1730s, a new operatic genre, opera buffa, emerged as an alternative to opera seria. It quickly made its way to France, where it became opéra comique, and eventually, in the following century, French operetta, with Jacques Offenbach as its most accomplished practitioner.

The masque was a form of festive courtly entertainment that flourished in 16th- and early 17th-century Europe, though it was developed earlier in Italy, in forms including the intermedio (a public version of the masque was the pageant). A masque involved music, dancing, singing and acting, within an elaborate stage design, in which the architectural framing and costumes might be designed by a renowned architect, to present a deferential allegory flattering to the patron. Professional actors and musicians were hired for the speaking and singing parts. Masquers who did not speak or sing were often courtiers: the English queen Anne of Denmark frequently danced with her ladies in masques between 1603 and 1611, and Henry VIII and Charles I of England performed in the masques at their courts. In the tradition of masque, Louis XIV of France danced in ballets at Versailles with music by Jean-Baptiste Lully.

Gioachino Antonio Rossini (29 February 1792 – 13 November 1868) was an Italian composer of the late Classical and early Romantic eras. He gained fame for his 39 operas, although he also wrote many songs, some chamber music and piano pieces and some sacred music. He set new standards for both comic and serious opera before retiring from large-scale composition while still in his thirties, at the height of his popularity.

Born in Pesaro to parents who were both musicians (his father a trumpeter, his mother a singer), Rossini began to compose by the age of twelve and was educated at music school in Bologna. His first opera was performed in Venice in 1810 when he was 18 years old. In 1815 he was engaged to write operas and manage theatres in Naples. In the period 1810–1823, he wrote 34 operas for the Italian stage that were performed in Venice, Milan, Ferrara, Naples and elsewhere; this productivity necessitated an almost formulaic approach for some components (such as overtures) and a certain amount of self-borrowing. During this period he produced his most popular works, including the comic operas L'italiana in Algeri, Il barbiere di Siviglia (known in English as The Barber of Seville) and La Cenerentola, which brought to a peak the opera buffa tradition he inherited from masters such as Wolfgang Amadeus Mozart, Domenico Cimarosa and Giovanni Paisiello. He also composed opera seria works such as Tancredi, Otello and Semiramide. All of these attracted admiration for their innovation in melody, harmonic and instrumental colour, and dramatic form. In 1824 he was contracted by the Opéra in Paris, for which he produced an opera to celebrate the coronation of Charles X, Il viaggio a Reims (later cannibalised for his first opera in French, Le comte Ory), revisions of two of his Italian operas, Le siège de Corinthe and Moïse, and in 1829 his last opera, Guillaume Tell.

The ballad opera is a genre of English comic opera stage play that originated in the early 18th century, and continued to develop over the following century and later. Like the earlier comédie en vaudeville and the later Singspiel, its distinguishing characteristic is the use of tunes in a popular style (either pre-existing or newly composed) with spoken dialogue. These English plays were 'operas' mainly insofar as they satirized the conventions of the imported opera seria. Music critic Peter Gammond describes the ballad opera as "an important step in the emancipation of both the musical stage and the popular song."

Christoph Willibald (Ritter von) Gluck (/ɡlʊk/; German: [ˈkʁɪstɔf ˈvɪlɪbalt ˈɡlʊk]; 2 July 1714 – 15 November 1787) was a composer of Italian and French opera in the early classical period. Born in the Upper Palatinate and raised in Bohemia, both part of the Holy Roman Empire at the time, he gained prominence at the Habsburg court in Vienna. There he brought about the practical reform of opera's dramaturgical practices for which many intellectuals had been campaigning. With a series of radical new works in the 1760s, among them Orfeo ed Euridice and Alceste, he broke the stranglehold that Metastasian opera seria had enjoyed for much of the century. Gluck introduced more drama by using orchestral recitative and cutting the usually long da capo aria. His later operas have half the length of a typical baroque opera.

The strong influence of French opera encouraged Gluck to move to Paris in November 1773. Fusing the traditions of Italian opera and the French (with rich chorus) into a unique synthesis, Gluck wrote eight operas for the Parisian stage. Iphigénie en Tauride (1779) was a great success and is often considered to be his finest work. Though he was extremely popular and widely credited with bringing about a revolution in French opera, Gluck's mastery of the Parisian operatic scene was never absolute. After the poor reception of his Echo et Narcisse (1779), he left Paris in disgust and returned to Vienna to live out the remainder of his life.

Domenico Gaetano Maria Donizetti (29 November 1797 – 8 April 1848) was an Italian composer, best known for his over 70 operas. Along with Gioachino Rossini and Vincenzo Bellini, he was a leading composer of the bel canto opera style during the first half of the nineteenth century and a probable influence on other composers such as Giuseppe Verdi. Donizetti was born in Bergamo in Lombardy. At an early age he was taken up by Simon Mayr who enrolled him with a full scholarship in a school which he had set up. There he received detailed musical training. Mayr was instrumental in obtaining a place for Donizetti at the Bologna Academy, where, at the age of 19, he wrote his first one-act opera, the comedy Il Pigmalione, which may never have been performed during his lifetime.

An offer in 1822 from Domenico Barbaja, the impresario of the Teatro di San Carlo in Naples, which followed the composer's ninth opera, led to his move to Naples and his residency there until production of Caterina Cornaro in January 1844. In all, 51 of Donizetti's operas were presented in Naples. Before 1830, success came primarily with his comic operas, the serious ones failing to attract significant audiences. His first notable success came with an opera seria, Zoraida di Granata, which was presented in 1822 in Rome. In 1830, when Anna Bolena was first performed, Donizetti made a major impact on the Italian and international opera scene shifting the balance of success away from primarily comedic operas, although even after that date, his best-known works included comedies such as L'elisir d'amore (1832) and Don Pasquale (1843). Significant historical dramas did succeed; they included Lucia di Lammermoor (the first to have a libretto written by Salvadore Cammarano) given in Naples in 1835, and one of the most successful Neapolitan operas, Roberto Devereux in 1837. Up to that point, all of his operas had been set to Italian libretti.