Sound

Sound is used in film to both create atmosphere and to make the audience aware of what is happening an/or about to happen in a scene.

The two main types of sound are:

Diegetic
This type of sound is the type that you would hear if you were in the scene with the characters. It is the sound you experience in normal life. Some examples are birds singing, people talking and car engines.
Some music can be diegetic if a character turns on a radio, for example.

Non-Diegetic
This type of sound is artificial sound that you would not hear if you were in the scene. Non-Diegetic sound is added during editing to add an extra effect or to help create a mood. The main type of this sound is Music.
Although some sounds are added after filming e.g. explosion if the sound would be heard by the characters it is not a Non-Diegetic sound.

There are other types of sound such as:
Parallel Sound
This type of sound is where the sound matches the mood of the scene it has been added to. In horror movies an example of Parallel sound would be edgy,dramatic music.

Contrapuntal Sound
This is where the sound does not match the mood of the scene, for example, light, happy music during a murder scene. This type of sound is used to confuse the audience and to also make them pay closer attention.

Sound Bridge
This is where the sound, usually music, carries on from one scene to the other. This is used to help link scenes especially during Jump Cuts.