What is non- diegetic sound mean?

Non-diegetic sound is sound that originates from a source outside the film's world. It is not natural to the scene or the environment in which it is placed. Non-diegetic sound is often used to create atmosphere, emotion, or to provide information about the setting or characters.

It is not tied to a visible source within the film. For example, the score of a film is a form of non-diegetic sound. It is not heard by the characters in the film, but is added in post-production to enhance the viewer's experience. Other examples of non-diegetic sound include sound effects, voice-overs, and music.

Here are some specific examples of non-diegetic sound:

- A voice-over narration provides background information about the characters or events in the film.

- A sound effect, such as a thunderclap, is used to create atmosphere or to underscore a moment of tension.

- Music is used to set the mood or tone of a scene, or to create a sense of drama or excitement.

Non-diegetic sound is an important tool for filmmakers to use to enhance the storytelling and create a more immersive experience for the audience.