The main difference between Sonata and Concerto is that the Sonata is a composition for one or more solo instruments and Concerto is a musical composition usually in three parts.
Sonata (; Italian: [soˈnaːta], pl. sonate; from Latin and Italian: sonare, “to sound”), in music, literally means a piece played as opposed to a cantata (Latin and Italian cantare, “to sing”), a piece sung. The term evolved through the history of music, designating a variety of forms until the Classical era, when it took on increasing importance, and is vague. By the early 19th century, it came to represent a principle of composing large-scale works. It was applied to most instrumental genres and regarded—alongside the fugue—as one of two fundamental methods of organizing, interpreting and analyzing concert music. Though the musical style of sonatas has changed since the Classical era, most 20th- and 21st-century sonatas still maintain the same structure.
The term sonatina, pl. sonatine, the diminutive form of sonata, is often used for a short or technically easy sonata.
A concerto (; plural concertos, or concerti from the Italian plural) is a musical composition usually composed in three movements, in which, usually, one solo instrument (for instance, a piano, violin, cello or flute) is accompanied by an orchestra or concert band. It is accepted that its characteristics and definition have changed over time. In the 17th century, sacred works for voices and orchestra were typically called concertos, as reflected by J. S. Bach’s usage of the title “concerto” for many of the works that we know as cantatas.
A musical composition for one or a few instruments, one of which is frequently a piano, in three or four movements that vary in key and tempo
A piece of music for one or more solo instruments and orchestra.