sounds

non-diegetic sounds
these sounds that appear to come from elsewhere/outside the visual images.

diegetic sounds
are sounds that belong naturally with what can be seen in the picture

sound effects consist of sounds that objects make, sounds that people make other than spoken words and ambient sounds.
some of the many possible uses of sound effects are to help create a sense of: location, intensity, mood, enhance a humorous situation or conceal an action.
sound effects specialists have many options in manipulating sounds, such as:playing them backwards, playing them faster or slower than they were recorded, constructing them and blending them in with different proportions.