Ensemble consisting of two violins, viola, and cello, or a work written for such an ensemble.
Since с 1775 such works have been perhaps the predominant genre of chamber music . It was principally developed (if not quite invented) by Wolfgang Amadeus Mozart , Ludwig van Beethoven , Franz Schubert , Béla Bartók , and Dmitry Shostakovich are the preeminent subsequent quartet composers. Works called string quartets have traditionally observed the four-movement design of the {{link=sonata">sonata and symphony . Like most chamber music genres, quartet music was traditionally intended primarily for the private enjoyment of amateur musicians rather than for public performance.