Chamber music evolved from the French chanson, a vocal music comprising of four voices accompanied by a lute. In Italy, the chanson became known as canzona and evolved from its original form of vocal music into instrumental music often adapted for the organ.
From the sonatas, specifically the trio sonatas, (ex. works by Arcangelo Corelli) evolved the string quartet which uses two violins, a cello and viola. Examples of string quartets are works by Franz Joseph Haydn.
In 1770, the harpsichord was replaced by the piano and the latter became a chamber music instrument. The piano trio (piano, cello and violin) then emerged evident in the works of Wolfgang Amadeus Mozart, Ludwig van Beethoven and Franz Schubert.
In the late 19th century, the piano quartet (piano, cello, violin and viola) emerged with the works of such composers as Antonín Dvorák and Johannes Brahms. In 1842, Robert Schumann wrote a piano quintet (piano plus string quartet).
During the 20th century, chamber music took on new forms combining different instruments including the voice. Composers such as Béla Bartók (string quartet) and Anton von Webern contributed to this genre.
Listen to a sample of chamber music: Quintet in B minor, available at the Friends of Chamber Music website.