Choir in the context of Pipe organ

Singing is the art of creating music with the voice. It is the oldest form of musical expression, and the human voice can be considered the first musical instrument by some. The definition of singing varies across sources. Some sources define singing as the act of creating musical sounds with the voice. Other common definitions include "the utterance of words or sounds in tuneful succession" or "the production of musical tones by means of the human voice".

A person whose profession (or hobby) is singing is called a singer or a vocalist (in jazz or popular music). Singers perform music (arias, recitatives, songs, etc.) that can be sung with or without accompaniment by musical instruments. Singing is often done in an ensemble of musicians, such as a choir. Singers may perform as soloists or accompanied by anything from a single instrument (as in art songs or some jazz styles) up to a symphony orchestra or big band. Many styles of singing exist throughout the world.

Wilhelm Richard Wagner (/ˈvɑːɡnər/ VAHG-nər; German: [ˈvɪlˌhɛlm ˈʁɪçaʁt ˈvaːɡnɐ] ; 22 May 1813 – 13 February 1883) was a German composer, theatre director, essayist, and conductor, best known for his operas—although his mature works are often referred to as music dramas. Unlike most composers, Wagner wrote both the libretti and the music for all of his stage works. He first achieved recognition with works in the Romantic tradition of Carl Maria von Weber and Giacomo Meyerbeer, but revolutionised the genre through his concept of the Gesamtkunstwerk ("total work of art"), which sought to unite poetic, musical, visual, and dramatic elements. In this approach, the drama unfolds as a continuously sung narrative, with the music evolving organically from the text rather than alternating between arias and recitatives. Wagner outlined these ideas in a series of essays published between 1849 and 1852, most fully realising them in the first half of his four-opera cycle Der Ring des Nibelungen (The Ring of the Nibelung).

Wagner's compositions, particularly in his later period, have complex textures, rich harmonies and orchestration, and elaborate leitmotifs—musical phrases associated with individual characters, places, ideas, or plot elements. His advances in musical language, such as extreme chromaticism and quickly shifting tonal centres, greatly influenced the development of classical music; his Tristan und Isolde is regarded as an important precursor to modernist music. Later in life, he softened his ideological stance against traditional operatic forms (e.g., arias, ensembles and choruses), reintroducing them into his last few stage works, including Die Meistersinger von Nürnberg (The Mastersingers of Nuremberg) and Parsifal.

A musical ensemble, also known as a music group, musical group, or a band is a group of people who perform instrumental and/or vocal music, with the ensemble typically known by a distinct name. Some music ensembles consist solely of instrumentalists, such as the jazz quartet or the orchestra. Other music ensembles consist solely of singers, such as choirs and doo-wop groups. In both popular music and classical music, there are ensembles in which both instrumentalists and singers perform, such as the rock band or the Baroque chamber group for basso continuo (harpsichord and cello) and one or more singers. In classical music, trios or quartets either blend the sounds of musical instrument families (such as piano, strings, and wind instruments) or group instruments from the same instrument family, such as string ensembles (e.g., string quartet) or wind ensembles (e.g., wind quintet). Some ensembles blend the sounds of a variety of instrument families, such as the orchestra, which uses a string section, brass instruments, woodwinds, and percussion instruments, or the concert band, which uses brass, woodwinds, and percussion. In jazz ensembles or combos, the instruments typically include wind instruments (one or more saxophones, trumpets, etc.), one or two chordal "comping" instruments (electric guitar, acoustic guitar, piano, or Hammond organ), a bass instrument (bass guitar or double bass), and a drummer or percussionist. Jazz ensembles may be solely instrumental, or they may consist of a group of instruments accompanying one or more singers. In rock and pop ensembles, usually called rock bands or pop bands, there are usually guitars and keyboards (piano, electric piano, Hammond organ, synthesizer, etc.), one or more singers, and a rhythm section made up of a bass guitar and drum kit.

Music ensembles typically have a leader. In jazz bands, rock and pop groups, and similar ensembles, this is the band leader. In classical music, orchestras, concert bands, and choirs are led by a conductor. In orchestra, the concertmaster (principal first violin player) is the instrumentalist leader of the orchestra. In orchestras, the individual sections also have leaders, typically called the "principal" of the section (e.g., the leader of the viola section is called the "principal viola"). Conductors are also used in jazz big bands and in some very large rock or pop ensembles (e.g., a rock concert that includes a string section, a horn section, and a choir that accompanies a rock band's performance).

Conducting is the art of directing a musical performance, such as an orchestral or choral concert. It has been defined as "the art of directing the simultaneous performance of several players or singers by the use of gesture." The primary duties of the conductor are to interpret the score in a way that reflects the specific indications in that score, set the tempo, ensure correct entries by ensemble members, and "shape" the phrasing where appropriate. Conductors communicate with their musicians primarily through hand gestures, usually with the aid of a baton, and may use other gestures or signals such as facial expression and eye contact. A conductor usually supplements their direction with verbal instructions to their musicians in rehearsal.

The conductor typically stands on a raised podium with a large music stand for the full score, which contains the musical notation for all the instruments or voices. Since the mid-19th century, most conductors have not played an instrument when conducting, although in earlier periods of classical music history, leading an ensemble while playing an instrument was common. In Baroque music, the group would typically be led by the harpsichordist or first violinist (concertmaster), an approach that in modern times has been revived by several music directors for music from this period. Conducting while playing a piano or synthesizer may also be done with musical theatre pit orchestras. Instrumentalists may perform challenging works while conducting - for instance, it is not uncommon to see a pianist perform a concerto while also conducting the orchestra. Communication is typically non-verbal during a performance. However, in rehearsals, frequent interruptions allow the conductor to give verbal directions as to how music should be performed.

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.

In music, monophony is the simplest of musical textures, consisting of a melody (or "tune"), typically sung by a single singer or played by a single instrument player (e.g., a flute player) without accompanying harmony or chords. Many folk songs and traditional songs are monophonic. A melody is also considered to be monophonic if a group of singers (e.g., a choir) sings the same melody together at the unison (exactly the same pitch) or with the same melody notes duplicated at the octave (such as when men and women sing together). If an entire melody is played by two or more instruments or sung by a choir with a fixed interval, such as a perfect fifth, it is also said to be monophony (or "monophonic"). The musical texture of a song or musical piece is determined by assessing whether varying components are used, such as an accompaniment part or polyphonic melody lines (two or more independent lines).

In the Early Middle Ages, the earliest Christian songs, called plainchant (a well-known example is Gregorian chant), were monophonic. Even into the twenty-first century, songwriters still often write songs that intersperse sections using monophony, heterophony (two singers or instrumentalists doing varied versions of the same melody together), polyphony (two or more singers or instrumentalists playing independent melodic lines at the same time), homophony (a melody accompanied by chords), or monody (a single melodic line with instrumental accompaniment) elements throughout the melody to create different atmospheres and styles. Monophony may not have underlying rhythmic textures, and must consist of only a single melodic line.

A part in music refers to a component of a musical composition. Because there are multiple ways to separate these components, there are several contradictory senses in which the word "part" is used:

• any individual melody (or voice), whether vocal or instrumental, that can be abstracted as continuous and independent from other notes being performed simultaneously in polyphony. Within the music played by a single pianist, one can often identify outer parts (the top and bottom parts) or an inner part (those in between). On the other hand, within a choir, "outer parts" and "inner parts" would refer to music performed by different singers. (See § Polyphony and part-writing)
• the musical instructions for any individual instrument or voice (often given as a handwritten, printed, or digitized document) of sheet music (as opposed to the full score which shows all parts of the ensemble in the same document). A musician's part usually does not contain instructions for the other players in the ensemble, only instructions for that individual.
• the music played by any group of musicians who all perform together for a given piece; in a symphony orchestra, a dozen or more cello players may all play "the same part" even if they each have their own physical copy of the music. This part may be in unison or may be harmonized, and may even sometimes contain counter-melodies within it. A percussion part may sometimes only contain rhythm. This sense of "part" does not require a written copy of the music; a bass player in a rock band "plays the bass part" even if there is no written version of the song.
• a section in the large-scale form of a piece. (See § Musical form)

Wolfgang Amadeus Mozart (27 January 1756 – 5 December 1791) was a prolific and influential composer of the Classical period. Despite his short life, his rapid pace of composition and proficiency from an early age resulted in more than 800 works representing virtually every Western classical genre of his time. Many of these compositions are acknowledged as pinnacles of the symphonic, concertante, chamber, opera, and choral repertoires. Mozart is widely regarded as one of the greatest composers in the history of Western music, with his music admired for its "melodic beauty, its formal elegance and its richness of harmony and texture".

Born in Salzburg, Mozart showed prodigious ability from his earliest childhood. At age five, he was already competent on keyboard and violin, had begun to compose, and performed before European royalty. His father, Leopold Mozart, took him on a grand tour of Europe and then three trips to Italy. At 17, he was a musician at the Salzburg court but grew restless and travelled in search of a better position. Mozart's fruitless journey in search of employment led him to Paris, Mannheim, Munich, and eventually back to Salzburg. During this time he wrote his five violin concertos, the Sinfonia Concertante, and Concerto for Flute and Harp, as well as sacred pieces and masses, the motet Exsultate Jubilate, and the opera Idomeneo, among other works.

Nine Lessons and Carols, also known as the Festival of Nine Lessons and Carols and Service of Nine Lessons and Carols, is a service of Christian worship traditionally celebrated on or near Christmas Eve in Anglican churches and globally within the Anglican Communion. The story of the fall of humanity, the promise of the Messiah, and the birth of Jesus is told in nine short Bible readings or lessons from Genesis, the prophetic books and the Gospels, interspersed with the singing of Christmas carols, hymns and choir anthems.

The Paris Opera (French: Opéra de Paris [ɔpeʁa də paʁi] ) is the primary opera and ballet company of France. It was founded in 1669 by Louis XIV as the Académie d'Opéra, and shortly thereafter was placed under the leadership of Jean-Baptiste Lully and officially renamed the Académie Royale de Musique, but continued to be known more simply as the Opéra. Classical ballet as it is known today arose within the Paris Opera as the Paris Opera Ballet and has remained an integral and important part of the company. Currently called the Opéra national de Paris, it mainly produces operas at its modern 2,723-seat theatre Opéra Bastille which opened in 1989, and ballets and some classical operas at the older 1,979-seat Palais Garnier which opened in 1875. Small scale and contemporary works are also staged in the 500-seat Amphitheatre under the Opéra Bastille.

The company's annual budget is in the order of 200 million euros, of which €100M come from the French state and €70M from box office receipts. With this money, the company runs the two houses and supports a large permanent staff, which includes the orchestra of 170, a chorus of 110 and the corps de ballet of 150.

The Symphony No. 9 in D minor, Op. 125, is a choral symphony, the final complete symphony by Ludwig van Beethoven, composed between 1822 and 1824. It was first performed in Vienna on 7 May 1824. The symphony is regarded by many critics and musicologists as a masterpiece of Western classical music and one of the supreme achievements in the history of music. One of the best-known works in common practice music, it stands as one of the most frequently performed symphonies in the world.

The Ninth was the first example of a major composer scoring vocal parts in a symphony. The final (4th) movement of the symphony, commonly known as the Ode to Joy, features four vocal soloists and a chorus in the parallel key of D major. The text was adapted from the "An die Freude (Ode to Joy)", a poem written by Friedrich Schiller in 1785 and revised in 1803, with additional text written by Beethoven. In the 20th century, an instrumental arrangement of the chorus was adopted by the Council of Europe, and later the European Union, as the Anthem of Europe.

A soprano (Italian pronunciation: [soˈpraːno]) is a type of classical singing voice and has the highest vocal range of all voice types. The soprano's vocal range (using scientific pitch notation) is from approximately middle C (C₄) = 261 Hz to A₅ in choral music, or to soprano C (C₆) or higher in operatic music. In four-part chorale style harmony, the soprano takes the highest part, which often encompasses the melody. The soprano voice type is generally divided into the coloratura, soubrette, lyric, spinto, and dramatic soprano.

The Schola Cantorum was the trained papal choir during the Middle Ages, specializing in the performance of plainchant for the purpose of rendering the music in church. In the fourth century, Pope Sylvester I was said to have inaugurated the first Schola Cantorum, but it was Pope Gregory I who established the school on a firm basis and endowed it. The choir ranged anywhere from twenty to thirty boys or men. Only the most skilled in singing were selected to participate in the Schola Cantorum.

Congregational singing is the practice of the congregation participating in the music of a church, either in the form of hymns or a metrical Psalms or a free form Psalm or in the form of the office of the liturgy (for example Gregorian chants). It is contrasted with music being sung exclusively by a choir or cantor(s). Congregational singing was largely the invention of the Protestant Reformation. Before then, singing in churches, especially in larger urban churches, was largely left to professionals. The reformers in Strasbourg, in particular, reduced the church service largely to a sermon bookended by congregational singing and prayers.

A chorale is the name of several related musical forms originating in the music genre of the Lutheran chorale:

• Hymn tune of a Lutheran hymn (e.g. the melody of "Wachet auf, ruft uns die Stimme"), or a tune in a similar format (e.g. one of the themes in the Finale of Saint-Saëns's Third Symphony)
• Such tune with a harmonic accompaniment (e.g. chorale monody, chorales included in Schemellis Gesangbuch)
• Such a tune presented in a homophonic or homorhythmic harmonisation, usually four-part harmony (e.g. Bach's four-part chorales, or the chorale included in the second movement of Mahler's Fifth Symphony)
• A more complex setting of a hymn-like tune (e.g. chorale fantasia form in Bach's Schübler Chorales, or a combination of compositional techniques in César Franck's Three Chorales [fr])

The chorale originated when Martin Luther translated sacred songs into the vernacular language (German), contrary to the established practice of church music near the end of the first quarter of the 16th century. The first hymnals according to Luther's new method were published in 1524. Luther and his followers not only wrote metrical hymn lyrics, but also composed metrical musical settings for these texts. This music was partially based on established melodies of church hymns and known secular songs. In the 17th century the repertoire was enriched with more choral and organ settings of the chorale tunes. By the end of the century a four-part setting for SATB voices had become the standard for the choral settings, while the congregational singing of chorales was tending towards monody with an instrumental accompaniment. The prolific creation of new Lutheran chorale tunes ended around that time.

An oratorio (Italian pronunciation: [oraˈtɔːrjo]) is a musical composition with dramatic or narrative text for choir, soloists and orchestra or other ensemble.

Similar to opera, an oratorio includes the use of a choir, soloists, an instrumental ensemble, various distinguishable characters (e.g. soloists), and arias. However, opera is musical theatre, and typically involves significant theatrical spectacle, including sets, props, and costuming, as well as staged interactions between characters. In oratorio, there is generally minimal staging, with the chorus often assuming a more central dramatic role, and the work is typically presented as a concert piece – though oratorios are sometimes staged as operas, and operas are not infrequently presented in concert form.