Although nearly half of Bachs 1,100 surviving compositions, arrangements, and transcriptions are instrumental works, only about 4% are sonatas.The term sonata is also applied to the series of over 500 works for harpsichord solo, or sometimes for other keyboard instruments, by Domenico Scarlatti, originally published under the name Essercizi per il gravicembalo (Exercises for the Harpsichord). Most of these pieces are in one binary-form movement only, with two parts that are in the same tempo and use the same thematic material, though occasionally there will be changes in tempo within the sections. They are frequently virtuosic, and use more distant harmonic transitions and modulations than were common for other works of the time. They were admired for their great variety and invention. Both the solo and trio sonatas of Vivaldi show parallels with the concerti he was writing at the same time. He composed over 70 sonatas, the great majority of which are of the solo type; most of the rest are trio sonatas, and a very small number are of the multivoice type.The sonatas of Domenico Paradies are mild and elongated works with a graceful and melodious little second movement included. Classical period
The practice of the Classical period would become decisive for the sonata; the term moved from being one of many terms indicating genres or forms, to designating the fundamental form of organization for large-scale works. This evolution stretched over fifty years.
There was also in the early Classical period the possibility of using four movements, with a dance movement inserted before the slow movement, as in Haydns Piano sonatas No. 6 and No. 8. Mozarts sonatas were also primarily in three movements. Of the works that Haydn labelled piano sonata, divertimento, or partita in Hob XIV, seven are in two movements, thirty-five are in three, and three are in four; and there are several in three or four movements whose authenticity is listed as "doubtful." Composers such as Boccherini would publish sonatas for piano and obbligato instrument with an optional third movement—–in Boccherinis case, 28 cello sonatas. But increasingly instrumental works were laid out in four, not three movements, a practice seen first in string quartets and symphonies, and reaching the sonata proper in the early sonatas of Beethoven. However, two- and three-movement sonatas continued to be written throughout the Classical period: Beethovens opus 102 pair has a two-movement C major sonata and a three-movement D major sonata. Nevertheless, works with fewer or more than four movements were increasingly felt to be exceptions; they were labelled as having movements "omitted," or as having "extra" movements. Thus, the four-movement layout was by this point standard for the string quartet, and overwhelmingly the most common for the symphony. The usual order of the four movements was:

An allegro, which by this point was in what is called sonata form, complete with exposition, development, and recapitulation. A slow movement, an Andante, an Adagio or a Largo.