A quintet is a piece written for five instruments or five singers. It can also be an ensemble that performs such works. Quintets are one of the most prominent forms of chamber music. Among the most common types are string quintets, wind quintets, brass quintets and piano quintets. Unlike the others, which commonly consist of instruments of a single category, piano quintets usually contain just a single piano, and the other four instruments are typically two violins, a viola and a cello.