A show tune is a song originally written as part of the score of a work of musical theatre or musical film, especially if the piece in question has become a standard, more or less detached in most people's minds from the original context.
Though show tunes vary in style, they do tend to share common characteristics—they usually fit the context of a story being told in the original musical, they are useful in enhancing and heightening choice moments. A particularly common form of show tune is the "I Want" song, which composer Stephen Schwartz noted as being particularly likely to have a lifespan outside the show that spawned it.
