History
Baroque
In the works of Arcangelo Corelli and his contemporaries, two broad classes of sonata were established, and were first described by Sébastien de Brossard in his Dictionaire de musique (third edition, Amsterdam, ca. 1710): the sonata da chiesa (that is, suitable for use in church), which was the type "rightly known as Sonatas", and the sonata da camera (proper for use at court), which consists of a prelude followed by a succession of dances, all in the same key. : 21, 40  Although the four, five, or six movements of the sonata da chiesa are also most often in one key, one or two of the internal movements are sometimes in a contrasting tonality.The sonata da chiesa, generally for one or more violins and bass, consisted normally of a slow introduction, a loosely fugued allegro, a cantabile slow movement, and a lively finale in some binary form suggesting affinity with the dance-tunes of the suite. This scheme, however, was not very clearly defined, until the works of Arcangelo Corelli when it became the essential sonata and persisted as a tradition of Italian violin music. The sonata da camera consisted almost entirely of idealized dance-tunes. On the other hand, the features of sonata da chiesa and sonata da camera then tended to be freely intermixed.
Scholarship and musicology
Sonata idea or principle
Research into the practice and meaning of sonata form, style, and structure has been the motivation for important theoretical works by Heinrich Schenker, Arnold Schoenberg, and Charles Rosen among others; and the pedagogy of music continued to rest on an understanding and application of the rules of sonata form as almost two centuries of development in practice and theory had codified it. The development of the classical style and its norms of composition formed the basis for much of the music theory of the 19th and 20th centuries. As an overarching formal principle, sonata was accorded the same central status as Baroque fugue; generations of composers, instrumentalists, and audiences were guided by this understanding of sonata as an enduring and dominant principle in Western music. The sonata idea begins before the term had taken on its present importance, along with the evolution of the Classical periods changing norms. The reasons for these changes, and how they relate to the evolving sense of a new formal order in music, is a matter to which research is devoted.