A soundtrack is a recorded audio signal that is matched in timing with the images in a book, play, movie, radio show, TV program, or video game. It can also refer to a music album that includes songs from a movie, video, or TV show. Additionally, it may describe the physical part of a film that holds the synchronized recorded sound.

In movie industry terms, a soundtrack is an audio recording made during film production or after it is finished. At first, dialogue, sound effects, and music in a film each have their own separate tracks. These are combined to create a composite track, which is what people hear in the film. When movies are re-recorded in another language, a dubbing track is created. This is also called an M&E (music and effects) track. M&E tracks include all sounds except dialogue, which is later added by the foreign distributor in the local language.

Dictionaries today list "soundtrack" as both a noun and a verb. The term was first used in the magazine Photoplay in 1929. A 1992 dictionary entry in the Academic Press Dictionary of Science and Technology did not separate the terms "sound track" and "soundtrack."

The term "soundtrack" became widely known with the introduction of soundtrack albums in the late 1940s. Movie companies first created these albums as a way to promote new films. These recordings were labeled as "music from the original motion picture soundtrack" or "music from and inspired by the motion picture." Over time, these phrases were shortened to "original motion picture soundtrack." These recordings are usually made from a film's music track, as they often include only isolated music from the film, not the full composite track with dialogue and sound effects.

The term "original soundtrack" (OST) is often used for music albums. It helps distinguish music created specifically for a film from later re-recordings or covers. OSTs are a type of concept album that focuses on a unified theme from a story.

Types of recordings

Types of soundtrack recordings include:

• Musical film soundtracks are for movies based on musical theatre. These focus mainly on the songs. (Examples: Grease, Evita)
• Film scores include instrumental music and background themes from movies. (Examples: Blade Runner, Star Wars series)
• Some movies mix orchestral film scores with pop songs. Both types of music are included. (Examples: Shrek series, Back to the Future series)
• Albums of popular songs played in the background of non-musical movies. (Examples: Top Gun, The Bodyguard)
• Video game soundtracks are released after the game is made. They include music from the game’s levels, menus, and other parts. (Examples: Final Fantasy VII, Red Dead Redemption 2)
• Albums that include both music and dialogue from the film. (Examples: Reservoir Dogs, A Star Is Born)

The soundtrack for the 1937 Walt Disney animated film Snow White and the Seven Dwarfs was the first film soundtrack sold to the public. It was released by RCA Victor Records on multiple 78 rpm discs in January 1938 as Songs from Walt Disney's Snow White and the Seven Dwarfs. This album has been reissued many times since its release.

The first live-action musical film with a commercially sold soundtrack was MGM’s 1946 film Till the Clouds Roll By, about composer Jerome Kern. The album was originally sold as four 10-inch 78 rpm records. Only eight songs from the film were included in the first version. Because there was no tape at the time, the record producer had to copy and re-copy music from playback discs used during filming. This process made the sound quality poor. The recordings were intentionally made without reverb so they would not sound too hollow in movie theaters.

MGM Records called these albums "original cast albums," similar to how Decca did for Broadway shows. This was because the music on the discs did not match the film’s timing. In contrast, "original motion picture soundtracks" would include music that could be played alongside the film. However, over time, the difference between these terms became unclear.

In the 1970s, 1980s, and 1990s, the phrase "recorded directly from the soundtrack" was used to describe music that matched the film’s timing. However, this term became unclear because some film music was made up of multiple attempts at a song. For example, if the original version of a song used in the film was not available, alternate recordings might be used instead.

Because of these unclear terms, the word "soundtrack" began to be used for any film music, whether recorded during filming or later in the studio. The term is also sometimes used for Broadway cast recordings.

Some projects, like The Sound of Music Live!, added to this confusion. The album released before the 2013 NBC special included studio recordings of the original cast. Only the instrumental parts of the music matched the special, but the live vocals did not. This created a technical challenge for creating a complete soundtrack.

Among MGM’s most famous soundtrack albums were those for films like 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 score albums became popular during the LP era, though some were sold on 78 rpm records earlier. Alex North’s score for the 1951 film A Streetcar Named Desire was released on a 10-inch LP by Capitol Records. It sold well and was later reissued on a 12-inch LP with music by Max Steiner on the other side.

Max Steiner’s score for Gone with the Wind has been recorded many times. In 1967, MGM Records released an album of the score recorded directly from the film. This version was enhanced for stereo sound. Recently, Rhino Records released a 2-CD set of the complete score in its original mono format.

One of the most popular film scores of all time is John Williams’ music from Star Wars. Many film score albums are no longer in print after the films are released, and some have become rare collector’s items.

In rare cases, entire film dialogue tracks were released on records. For example, the 1968 film Romeo and Juliet was sold as a 4-LP set, a single LP with musical and dialogue excerpts, and an album with only the film’s music. The film Who’s Afraid of Virginia Woolf? was released as a 2-LP set with most of the film’s dialogue. Similarly, RCA Victor, Decca Records, and Disney Music Group released double-album sets with dialogue from A Man for All Seasons, Man of La Mancha, and The Hobbit.

Film and television soundtracks

When a popular movie comes out or after a TV show is broadcast, a soundtrack album is often released at the same time.

A soundtrack usually includes music played during a film or TV show, such as a film score. It may also include songs sung by characters in scenes, songs used as background music in important moments, songs played during the closing credits, or songs added for promotion that are not directly connected to the media.

Soundtracks are typically released by major record companies, just like music from artists. The songs and the soundtrack itself can appear on music charts and may win awards.

By tradition, a soundtrack can include music inspired by a movie but not actually used in it. However, a film score only includes music written by the movie’s original composers.

Sometimes, a soundtrack breaks from usual patterns, especially in popular culture series. These soundtracks may include new or exclusive pop songs that have not been released before. Some of these songs become popular on their own because of their connection to the franchise. These soundtracks are often used to promote well-known or new artists, and the music in them is not played in the film or TV show. Any connection between the music and the media is by chance.

Depending on the type of media, soundtracks may follow certain patterns. For example, a romantic movie might include soft love songs, while a suspenseful thriller might use rock or urban music.

In 1908, Camille Saint-Saëns created the first music made specifically for a movie, L'assassinat du duc de Guise. By the 1930s, it became common to release recordings of songs from films. Henry Mancini, who won an Emmy and two Grammy Awards for his work on Peter Gunn, was the first composer to have a major hit with a song from a soundtrack.

Before the 1970s, soundtracks (except in a few cases) were used for musicals. These albums included songs performed by actors, either with vocals or instruments, or as instrumental versions of songs. They also included cover songs by other artists.

After the 1970s, soundtracks began to include more varied music. People started to expect music from movies and TV shows to be released as albums. Most of the top songs on music charts were from film or TV soundtracks.

In recent years, the term "soundtrack" has become less common. Now, it usually refers only to instrumental background music used in media. Songs from movies or TV shows that are popular are listed in credits, not as part of a soundtrack.

Psychology of music and film soundtracks

In the late 1980s, researchers in cognitive psychology and the psychology of music began studying how soundtracks affect how people understand videos or movies. Annabel J. Cohen, a Canadian psychologist, was one of the first scientists to carefully examine how music and moving images work together when people watch short animated videos. Her research led to the creation of the Congruence-Association Model of music and multimedia. More recent studies have shown that film music does more than just add emotions to movies; it can greatly change how viewers feel about characters, how they interpret emotions (such as whether a character is happy or sad), how they judge the settings in a film, their predictions about what will happen next, and their moral opinions about characters. Eye-tracking and pupil-measuring studies found that film music can influence where people look and how much their pupils expand, depending on the music's emotional tone and the meaning of its message. Recent experiments also showed that film music can change how people perceive time while watching movies. For example, music that is exciting or stimulating makes people think time has passed more slowly, while music that is calm or sad makes people think time has passed more quickly. Finally, studies have proven that soundtracks can shape how viewers remember scenes, sometimes making them recall details that match the music's meaning.

Video game soundtracks

A soundtrack can also mean the music used in video games. Sound effects were commonly used to show actions in games, but music to go along with the game was developed later. Rob Hubbard and Martin Galway were among the first composers to create music specifically for video games on the 1980s Commodore 64 computer. Koji Kondo was an early and important composer for Nintendo games. As technology improved, more complex music with multiple notes and orchestral sounds replaced simple single-note melodies starting in the late 1980s. Soundtracks from popular games like Dragon Quest and Final Fantasy were released on their own. In addition to music created for video games, the introduction of CD technology let developers use licensed songs in their soundtracks (the Grand Theft Auto series is an example of this). Additionally, when Microsoft released the Xbox in 2001, it had an option that let users change the soundtrack for certain games by copying a CD to the hard drive.

Theme park, cruise ship, and event soundtracks

In events like Sound of Music Live!, the music and dialogue were created specifically for that event. This means they were prepared for use during the event described above.

In theme parks, actors may wear large costumes that cover their faces. They perform along with a pre-recorded music, effects, and narration track. This track might sound like it is from a movie or be very dramatic for effect.

On cruise ships, small stages make it hard to have a full orchestra. Sometimes, larger instruments are recorded ahead of time, and smaller ones are played live. Other times, the opposite happens, as seen in events like Elvis: The Concert or Sinatra: His Voice. His World. His Way. These events feature live bands and pre-recorded vocals or videos.

For large events like Hands Across America, The Live Aid Concert, the 200th Anniversary Celebration of the U.S. Constitution in Philadelphia, The MUSE Concerts, and Greenpeace events (such as The First International Greenpeace Record Project, Rainbow Warriors, and Alternative NRG), special music, effects, and dialogue were created. These were later sold to the public as records and videos.

Book soundtracks

Only a few examples exist of complete soundtracks created specifically for books.

One such example is Kaladin, a soundtrack for the book The Way of Kings by Brandon Sanderson. The music was composed by The Black Piper, a group of composers from Provo, Utah, who enjoy fantasy stories. The project was funded through Kickstarter and raised more than $112,000. The soundtrack was released in December 2017.

Another example is Green Rider, a book by Kristen Britain that has been a New York Times Bestseller. To celebrate its 25th anniversary, a soundtrack with the same name was created. The music was recorded in Utah and included artists Jenny Oaks Baker and William Arnold. It was released in 2018.

A soundtrack for J.R.R. Tolkien’s The Hobbit and The Lord of the Rings was composed by Craig Russell for the San Luis Obispo Youth Symphony. The project was commissioned in 1995 and released as a recording in 2000 by the San Luis Obispo Symphony.

For the 1996 Star Wars novel Shadows of the Empire, written by Steve Perry, Lucasfilm hired Joel McNeely to create a score. This project was unusual because the composer was allowed to express general feelings and themes rather than music tied to specific scenes. A project called "Sine Fiction" has created soundtracks for science fiction books by authors like Isaac Asimov and Arthur C. Clarke. It has released 19 soundtracks, all available for free download.

Author L. Ron Hubbard composed a soundtrack for his novel Battlefield Earth, titled Space Jazz. He promoted it as "the only original soundtrack ever made for a book before it became a movie." Two other soundtracks were created for his books: Mission Earth by Edgar Winter and To the Stars by Chick Corea.

The 1985 novel Always Coming Home by Ursula K. Le Guin originally came with a box set that included an audiocassette called Music and Poetry of the Kesh. It featured three poetry performances and ten musical pieces by Todd Barton.

In comics, Daniel Clowes’ graphic novel Like a Velvet Glove Cast in Iron had an official soundtrack. The original black-and-white comic Nexus #3 from Capitol Comics included a flexi-disc soundtrack for the issue. The graphic novel Trosper by Jim Woodring had a soundtrack composed and performed by Bill Frisell. The Absolute Edition of The League of Extraordinary Gentlemen: Black Dossier plans to include an original vinyl record. The comic The Crow released a soundtrack called Fear and Bullets to match its limited hardcover edition. The comic Hellblazer included a song called Venus of the Hardsell in an annual, which was later turned into a music video.

The Brazilian graphic novel Achados e Perdidos (Lost and Found), by Eduardo Damasceno and Luís Felipe Garrocho, had a soundtrack composed by musician Bruno Ito. The book was self-published in 2011 after a crowdfunding campaign and included a CD with eight songs, one for each chapter. In 2012, the graphic novel won the Troféu HQ Mix, Brazil’s top comic book award, in the "Special Homage" category.

As the Internet became more accessible, some books began to include downloadable theme songs instead of full physical soundtracks. Examples include Nextwave, Runaways, Achewood, and Dinosaur Comics. The 2019 novella Chasing Homer by László Krasznahorkai was published with an original soundtrack by Miklos Szilveszter, accessible through a QR code at the start of each chapter.

In Japan, music inspired by books but not tied to radio plays or movies is called an image album or image song. This term also includes music based on concept art or TV series that are not part of the original shows. Many audiobooks include some music, but it is usually not enough to be released as a separate soundtrack.