Sound Definitions

Sound in media is made up of two types of sound; diegetic and non-diegetic.
Diegetic is sound which can be heard by the audience and characters in the shot such as dialogue or sounds from objects. Whereas non-diegetic is sound which may only be heard by the audience such as narrative commentary, sound effects added for drama or mood music.

The pitch of music can also really effect the entire drama of the scene such as the high pitched strings in this famous scene of Psycho;