The term soundtrack refers to three related concepts: recorded music accompanying and synchronized to the images of a motion picture, television program or video game; a commercially released soundtrack album of music as featured in the soundtrack of a film or TV show; and the physical area of a film that contains the synchronized recorded sound.
The contraction soundtrack (one word) came into use with the advent of so-called "soundtrack albums" in the early 1950s. First conceived by movie companies as a promotional gimmick for new films, these commercially available recordings were labelled and advertised as "music from the original motion picture soundtrack." This phrase was soon shortened to just "original motion picture soundtrack." More accurately such recordings are made from a film's music track, because they usually consist of the isolated music from a film, not the composite (sound) track with dialogue and sound effects.
The abbreviation OST is often used to describe the musical soundtrack on a recorded medium, such as CD, and it stands for Original Soundtrack; however, it is sometimes also used to differentiate the original music heard and recorded versus a rerecording or cover of the music.
Soundtracks are not the same as "cast albums". Original cast recordings are studio made recordings of the songs from a stage musical. The performers sing the score live every night. They do not lip-synch to pre-recorded tracks. Incorrect use of the terminologies creates confusion in the marketplace. For example as of July 2008 there are two albums of the "Mamma Mia" score. The first is the original London cast recording from 1999, while the latest is the film soundtrack. While it is correct to call the soundtrack a cast recording (since it is the cast of the film version) it is incorrect to call the original London cast recording a soundtrack.
1. Musical film soundtracks which concentrate primarily on the songs
(Examples: “Grease”, “Singin' in the Rain”)
2. Film scores which showcase the background music from non-musicals (Examples: “Star Wars”, “”Exodus”)
3. Albums of pop songs heard in whole or part in the background of non-musicals (Examples: “Sleepless in Seattle”, “When Harry Met Sally”)
The first musical film to have a commercially issued soundtrack album was MGM’s film biography of Jerome Kern, “Till the Clouds Roll By” The album was originally issued as a set of four 10-inch 78-rpm records. Only eight selections from the film are included in this album. In order to fit the songs onto the record sides the musical material needed editing and manipulation. This was before tape existed, so the record producer needed to copy segments from the playback discs used on set, the copy and re-copy them from one disc to another adding transitions and cross-fades until the final master was created. Needless to say it was several generations removed from the original and the sound quality suffered for it. Also, the playback recordings were purposely recorded very "dry" (without reverberation) otherwise it would come across too hollow sounding in large movie theatres. This made these albums sound flat and boxy.
MGM Records called these "original cast albums" in the style of Decca's Broadway show cast albums. They also coined the phrase "recorded directly from the soundtrack." Over the years the term "soundtrack" began to be commonly applied to any recording from a film, whether taken from the actual film soundtrack or re-recorded in studio. The phrase is also sometimes incorrectly used for Broadway cast recordings. While it is correct to call a "soundtrack" a "cast recording" (since it represents the film cast) it is never correct to call a "cast recording" a "soundtrack." Among their most notable soundtrack albums were those of the films “Good News”, “Easter Parade ”, “Annie Get Your Gun”, Singin' in the Rain, Show Boat, “The Band Wagon”, “Seven Brides for Seven Brothers”, and “Gigi”.
Film scores albums did not really become popular until the LP era, although a few were issued in 78-rpm albums. Alex North’s score for the film version of “A Streetcar Named Desire” was released on a 10-inch LP by “Capitol Records” and sold so well that the label later re-released it on one side of a 12-inch LP with Max Steiner film music on the reverse.
Steiner’s score for “Gone with the Wind” has been recorded many times but when the film was reissued in 1967, MGM Records released an album of the famous score. One of the biggest-selling film scores of all time was John William’s music from the movie “Star Wars”. Many film score albums go out-of-print after the films finish their theatrical runs and some have become extremely rare collectors’ items.
In a few rare instances an entire film dialogue track was issued on records. The 1968 Franco Zefferelli film of “Romeo and Juliet” was issued as a 4-LP set, and also as a single LP with musical and dialogue excerpts. The ground-breaking film “ Who’s Afraid of Virginia Woolf?” was put out by Warner Bros Records as a 2-LP set containing the complete film play.
By convention, a soundtrack record can contain all kinds of music including music "inspired by" but not actually appearing in the movie; the score contains only music by the original film's composer(s).
A soundtrack for J. R. R. Tolkien's The Hobbit and his trilogy The Lord of the Rings was composed by Craig Russell for the San Luis Obispo Youth Symphony. Commissioned in 1995, it was finally put on disk in 2000 by the San Luis Obispo Symphony.
For the 1996 Star Wars novel Shadows of the Empire (written by author Steve Perry), Lucasfilm chose Joel McNeely to write a score. This was an eccentric, experimental project, in contrast to all other soundtracks, as the composer was allowed to convey general moods and themes, rather than having to write music to flow for specific scenes. A project called "Sine Fiction has made some soundtracks to novels by science fiction writers like Isaac Asimov and Arthur C. Clarke, and has thus far released 19 soundtracks to science-fiction novels or short stories. All of them are available for free download.
The 1985 novel Always Coming Home by Ursula K. Le Guin, originally came in a box set with an audiocassette entitled Music and Poetry of the Kesh, featuring three performances of poetry, and ten musical compositions by Todd Barton.
In comics, Daniel Clowes' graphic novel Like a Velvet Glove Cast in Iron had an official soundtrack album. The original black-and-white Nexus #3 from Capitol comics included the "Flexi-Nexi" which was a soundtrack flexi-disc for the issue. Trosper by Jim Woodring included a soundtrack album composed and performed by Bill Frisell, and the Absolute Edition of The League of Extraordinary Gentlemen: Black Dossier is planned to include an original vinyl record.
As Internet access became more widespread, a similar practice developed of accompanying a printed work with a downloadable theme song, rather than a complete and physically published album. The Nextwave theme song and the theme songs for the webcomics Achewood, Dinosaur Comics and Killroy and Tina are examples of this.
Many audio books have some form of musical accompaniment, but these are generally not complex enough to count as a complete soundtrack.