Key Words Glossary - SOUND

Diegetic Sound - sound whose source is visible on the screen or is implied to be present by the action of the film:

• voices of characters
• sounds made by objects in the story
• music represented as coming from instruments in the story space

Non-Diegetic Sound - sound which is not visible on screen and hasn't been implaid to be present in the action:

narrator's commentary

sound effects which is added for the dramatic effect

mood music

Soundtrack - a group of songs put inside a movie, which later can be released on a CD.

Theme - a melody which is used to identify a performer or a dance band or radio/tv programme.

Tune - a melody which characterizes a certain piece of music

Incidental music - a piece of music used in a film or play as a background to create or enhance a particular atmosphere.

Sound effects - created to enhance sounds or emphasize the content of films, TV shows etc.

Ambient s0und - in atmospheric sounding and noise pollution, ambient noise level (sometimes called background noise level, reference sound level, or room noise level) is the sound pressure level at a given location, normally specified as a reference level to study a new intrusive sound source.

Dialogue - conversation between two or more people as a feature of a book, play, or movie.

Voice-over - the voice on an unseen commentator in a film of television programme.

(Source: http://en.wikipedia.org/wiki/)