Joseph Haydn in the context of "Music of Germany"

In music theory, a phrase (Greek: φράση) is a unit of musical meter that has a complete musical sense of its own, built from figures, motifs, and cells, and combining to form melodies, periods and larger sections.

Terms such as sentence and verse have been adopted into the vocabulary of music from linguistic syntax. Though the analogy between the musical and the linguistic phrase is often made, still the term "is one of the most ambiguous in music....there is no consistency in applying these terms nor can there be...only with melodies of a very simple type, especially those of some dances, can the terms be used with some consistency."

Ludwig van Beethoven (baptised 17 December 1770 – 26 March 1827) was a German composer and pianist. One of the most revered figures in the history of Western music, his works rank among the most performed of the classical music repertoire and span the transition from the Classical period to the Romantic era. Beethoven's early period, during which he forged his craft, is typically considered to have lasted until 1802. From 1802 to around 1812, his middle period showed an individual development from the styles of Joseph Haydn and Wolfgang Amadeus Mozart, and is sometimes characterised as heroic. During this time, Beethoven began to grow increasingly deaf. In his late period, from 1812 to 1827, he extended his innovations in musical form and expression.

Born in Bonn, Beethoven displayed his musical talent at a young age. He was initially taught intensively by his father, Johann van Beethoven, and later by Christian Gottlob Neefe. Under Neefe's tutelage in 1783, he published his first work, a set of keyboard variations. He found relief from a dysfunctional home life with the family of Helene von Breuning, whose children he loved, befriended, and taught piano. At age 21, he moved to Vienna, which subsequently became his base, and studied composition with Haydn. Beethoven then gained a reputation as a virtuoso pianist, and was soon patronised by Karl Alois, Prince Lichnowsky for compositions, which resulted in his three Opus 1 piano trios (the earliest works to which he accorded an opus number) in 1795.

In music, a subject is the material, usually a recognizable melody, upon which part or all of a composition is based. In forms other than the fugue, this may be known as the theme.

The term string quartet is a type of musical composition or a group of four people who play them. Many composers from the mid-18th century onwards wrote string quartets. The associated musical ensemble consists of two violinists, a violist, and a cellist.

The string quartet was developed into its present form by the Austrian composer Joseph Haydn, whose works in the 1750s established the ensemble as a group of four more-or-less equal partners. Since that time, the string quartet has been considered a prestigious form; writing for four instruments with broadly similar characteristics both constrains and tests a composer. String quartet composition flourished in the Classical era, and Mozart, Beethoven and Schubert each wrote a number of them. Many Romantic and early-twentieth-century composers composed string quartets, including Mendelssohn, Schumann, Brahms, Dvořák, Janáček, and Debussy. There was a slight lull in string quartet composition later in the 19th century, but it received a resurgence in the 20th century, with the Second Viennese School, Bartók, Shostakovich, Babbitt, and Carter producing highly regarded examples of the genre, and it remains an important and refined musical form.

A wind quintet, also known as a woodwind quintet, is a group of five wind players (most commonly flute, oboe, clarinet, French horn and bassoon).

Unlike the string quartet (of 4 string instruments) with its homogeneous blend of sound color, the instruments in a wind quintet differ from each other considerably in technique, idiom, and timbre. The modern wind quintet sprang from the octet ensemble favored in the court of Joseph II in late 18th century Vienna: two oboes, two clarinets, two (natural) horns, and two bassoons. The influence of Haydn's chamber writing suggested similar possibilities for winds, and advances in the building of these instruments in that period made them more useful in small ensemble settings, leading composers to attempt smaller combinations.

A transition is a passage of music composed to link one section of music to another. Transitions often function as a moment of transformation and may, or may not in themselves, introduce new, musical material.

Often in music, the transition is the middle section or formal function, while the main theme is the beginning, and the subordinate theme is the ending. It may traditionally be a part of the sonata form's exposition in which the composer modulates from the key of the first subject to the key of the second, though many Classical era works move straight from first to second subject groups without any transition.

In music, development is a process by which a musical idea is transformed and restated in the course of a composition. Certain central ideas are repeated in different contexts or in altered form so that the listener can consciously or unconsciously compare the various statements of the idea, often in surprising or ironic manners. This practice has its roots in counterpoint, where a theme or subject might create an impression of a pleasing or affective sort, but delight the mind further as its contrapuntal capabilities are gradually unveiled in a fugal development

Johann Christian Bach (5 September 1735 – 1 January 1782) was a German composer of the Classical era, the youngest son of Johann Sebastian Bach. He received his early musical training from his father, and later from his half-brother, Carl Philipp Emanuel Bach in Berlin. After his time in Berlin he made his way to Italy to study with famous Padre Martini in Bologna. While in Italy, J.C. Bach was appointed as an organist at the Milan Cathedral. In 1762 he became a composer to the King’s Theatre in London where he wrote a number of successful Italian operas and became known as "The English Bach". He is responsible for the development of the sinfonia concertante form. He became one of the most influential figures of the classical period, influencing compositional styles of prolific composers like Joseph Haydn and Wolfgang Amadeus Mozart.