A piece of music designed to be played as an introduction,
e.g., to a liturgical ceremony or, more usually, to another composition,
such as a fugue or suite.
This connotation, which prevails throughout the entire early history of
the prelude, was lost in the 19th century, when Chopin,
and Debussy used the word
as one of numerous noncommittal titles for piano
pieces. With few exceptions, the prelude has always been
restricted to instrumental solo music, that is, to keyboard instruments
and the lute.