What is sound?

Sound is a film narrative used within films such as sound effects and background music. This can be categorized in any type of piece of audio that you do need or want in the film, it can replaced with the music and the sound effects. I also found that the use of sound is very useful for creating tensions and suspense throughout the film, as this can give the audience some action on the screen at some pace and the editor can process this by speeding up the sequences.

Sound is divided into two main categories, on of them being:
Digetic sound -  this is the sound that is used as a source of onscreen categorize, these examples can be sued in films such as:

Dialogue: a conversation that can be between two or more people that are presented in a  play or film
Sound effects: these are sounds that can be artificially as they can be played in the back or during a scene
Ambient sound: means the background music'sounds which are presented in a scene or in a location, these can be common ambient sounds that include wind, winter, crowds and also sounds from traffic etc.

Non-Digectic sounds - this would be the sounds that does not have an onscreen source and the characters onscreen that they do not hear. for example

Theme music: theme music is the piece of sound that is often written specially for a radio program, television program, video game on the movies and usually play during the intro, opening credits and the ending credits
Contrapuntal sound- when the sound we hear should usually go hand in hand with the image on screen.this is known on the Parallel sounds, for example: if we were to watch a horror film and we are about to witness
s murder, you would usually hear music that creates a suspense and an anxiety feeling as a surprising act would happen any minute and by creating that suspense bring excitement to the audience.