Title: List of opera genres
Content:  This is a glossary list of opera genres, giving alternative names. "Opera" is an Italian word (short for "opera in musica"); it was not at first commonly used in Italy (or in other countries) to refer to the genre of particular works. Most composers used more precise designations to present their work to the public. Often specific genres of opera were commissioned by theatres or patrons (in which case the form of the work might deviate more or less from the genre norm, depending on the inclination of the composer). Opera genres are not exclusive. Some operas are regarded as belonging to several.
Title: Opera
Content:  Opera is a form of theatre in which music is a fundamental component and dramatic roles are taken by singers, but is distinct from musical theatre. Such a "work" (the literal translation of the 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 
Title: List of opera topics
Content: Azione teatrale ; Ballad opera ; Chamber opera ; Comic opera ; Dramma giocoso ; Duodrama ; Farsa ; Festa teatrale ; Grand opera ; Literaturoper ; Monodrama ; Music drama ; Opéra-ballet ; Opera buffa ; Opéra bouffe ; Opéra bouffon ; Opéra comique ; Opéra féerie ; Opera semiseria ; Opera seria ; Operetta ; Pasticcio ; Pastorale héroïque ; Radio opera ; Rescue opera ; Romantische Oper ; Sainete ; Savoy opera ; Science fiction opera ; Semi-opera ; Singspiel ; Spieloper ; Tragédie en musique ; Verismo ; Zarzuela ; Zeitoper Over the centuries, the original form of opera, as established by Claudio Monteverdi and his contemporaries, has diversified into distinct and recognisable genres, in addition to the national traditions listed above. These include, but are not limited to, the following. 
Title: List of opera topics
Content:  Opera is an art form in which singers and musicians perform a dramatic work (called an opera), which combines a text (called a libretto) and a musical score. Opera is part of the Western classical music tradition. While the scale of opera can be larger or smaller—there are many different genres of opera—performance typically involves different types of artist (singers, instrumentalists and often dancers and actors) and technical staff. Usually an orchestra led by a conductor accompanies the singers. In contrast to spoken theatre, the opera world is international. Italian, German, French, English, and Russian works are performed worldwide in their original languages, and artists travel from country to country performing. The following is a list of articles on general opera topics:
Title: Operetta
Content:  Operetta is a form of theatre and a genre of light opera. It includes spoken dialogue, songs, and dances. It is lighter than opera in terms of its music, orchestral size, length of the work, and at face value, subject matter. Apart from its shorter length, the operetta is usually of a light and amusing character. It sometimes also includes satirical commentaries. "Operetta" is the Italian diminutive of "opera" and was used originally to describe a shorter, perhaps less ambitious work than an opera. Operetta provides an alternative to operatic performances in an accessible form targeting a different audience. Operetta became a recognizable form in the mid-1800s in France, and its popularity led to the development of many national styles of operetta. Distinctive styles emerged across countries including Austria-Hungary, Germany, England, Spain, the Philippines, Mexico, Cuba, and the United States. Through the transfer of operetta among different countries, cultural cosmopolitanism emerged in the previous century. Operetta as a genre lost favor in the 1930s and gave way to modern musical theatre. Important operetta composers include Johann Strauss, Jacques Offenbach, Franz Lehar, and Francisco Alonso.
Title: Rap opera
Content:  Rap opera, also known as hip-hopera, is a hybrid genre between rap and opera. Opera is a musical genre that began in the late 16th century. Hip hop is a much newer musical genre that became popular during the 1970s. Historically, both rap and opera have been used as a form of expression and storytelling. Now in popular culture, the fusion of the two genres is being used for the same purpose. Historically popular and classic pieces such as Carmen and Romeo and Juliet have been transformed into hip hop pieces.
Title: Opéra-ballet
Content:  Opéra-ballet (plural: opéras-ballets) is a genre of French Baroque lyric theatre that was most popular during the 18th century, combining elements of opera and ballet, "that grew out of the ballets à entrées of the early seventeenth century". It differed from the more elevated tragédie en musique as practised by Jean-Baptiste Lully in several ways. It contained more dance music than the tragédie, and the plots were not necessarily derived from classical mythology and allowed for the comic elements, which Lully had excluded from the tragédie en musique after Thésée (1675). The opéra-ballet consisted of a prologue followed by a number of self-contained 
Title: List of opera genres
Content:  Opera genres have been defined in different ways, not always in terms of stylistic rules. Some, like opera seria, refer to traditions identified by later historians, and others, like Zeitoper, have been defined by their own inventors. Other forms have been associated with a particular theatre, for example opéra comique at the theatre of the same name, or opéra bouffe at the Théâtre des Bouffes Parisiens. This list does not include terms that are vague and merely descriptive, such as "comic opera", "sacred opera", "tragic opera" or "one-act opera" etc. Original language terms are given to avoid the ambiguities that would be caused by English translations.
Title: Operatic pop
Content:  Operatic pop or popera is a subgenre of pop music that is performed in an operatic singing style or a song, theme or motif from classical music stylized as pop. The subgenre is often performed by classical crossover singers and acts, although that field is much broader in the types of music it encompasses. "Popera" performances, such as those by the Three Tenors, have reached larger audiences and brought in greater profits than typical for operatic music.
Title: Opéra comique
Content:  Opéra comique (plural: opéras comiques) is a genre of French opera that contains spoken dialogue and arias. It emerged from the popular opéras comiques en vaudevilles of the Fair Theatres of St Germain and St Laurent (and to a lesser extent the Comédie-Italienne), which combined existing popular tunes with spoken sections. Associated with the Paris theatre of the same name, opéra comique is not necessarily comical or shallow in nature; Carmen, perhaps the most famous opéra comique, is a tragedy.

Question: What genre is Opera?
Answer: horror film.
horror movie.