Music helps in making films effective. All throughout the history of cinema, it is incorporated in scenes for different purposes. It communicates the emotions that the director wants the audience to feel. It also builds suspense and directs people what to think. It forms a bond between the watcher and the movie or between the spectator and the narrator.

Aside from that, playing songs in films provide information regarding the plot, which may not be overtly evident through the images. It can also give a feeling of space or time. It emphasises various events and directs the flow of the movie scenes.

There are two categories for film music. The first is non-diegetic, which only the audience can hear and not the characters in the movie. Second is diegetic, wherein songs are used in the world of the motion picture. The actors and actresses can hear the melodies that may be played in bars, radios and sound systems.

Musical scores and soundtracks are also substantial players in advertising, animation and computer games.