What is an OST?
OST or Original Soundtrack refers to the music that accompanies scenes of a particular movie, TV series, video game, or even books. If a movie is involved then it is called an original movie soundtrack. For TV programs, they are called original TV program soundtrack.
In the case of movies, many of the scenes involved in a particular film have some sort of accompanying music. A scene featuring some dance moves by the characters in one movie will be so dull if no music is inserted in the movie. In this case, the music is the main highlight of the particular scene. In other sequences, music may play as a background to people having a dialogue. In horror and suspense movies, music may also serve as a prelude to a very important movie twist or event. There are also movies that involve the actors with singing parts. Like in the case of musicals, actors don’t just deliver lines, they sometimes sing their parts. In its entirety, one particular movie may have a dozen up to a hundreds of songs that are played at different parts and sequences. And in order for producers to further promote a particular movie, an OST or a soundtrack is sometimes released. A typical soundtrack includes the songs that are considered important and vital to the entire movie. Mostly the opening and ending songs are included in the compilation. Some companies and movie producers also opt to include only the songs with lyrics or the songs that were sung by the actors to be part of the OST compilation.
The movies were the first to use the term OST or soundtrack in the promotion of films. But besides the movies, other forms of media have also used soundtracks and/or OSTs for marketing and other reasons. These media include various TV programs, some books, and even video games.