Sound is a powerful and effective film technique that can affect, indicate and mould the audience on how you judge certain characters an example is, if the music soundtrack in the beginning of a film portrays a character as a hero or a leader the tempo would be yet if the music changes tempo he could be perceived a villain. 

Sound effects: Is a recorded sound that can be added to visuals in the editing process as well as other than speech or music that is which is included in the soundtrack to enhance and boost the narrative or make a creative statement.  The personal who is responsible for obtaining all sound effects and essential component of the production is a sound designer.

Diegetic sound: Is any sound that the characters on screen can hear, therefore is actual sound that can vary both on screen and off screen. Also comes from an object or a person in the story space. For instance in Jaws (1975) the sound of waves, a character shouting and a child playing with sand would be diegetic, furthermore the sounds of the characters speaking.

Non-diegetic Sound: Means all sound that the audience can hear however the characters on screen are unable to. This type of sound is added later in the editing process, an example is voiceover soundtrack music that is added for creative use within a scene. A source that is outside the narrative space even a voiceover narration I.e guards of the galaxy (2014) a scene with Chris pit who plays (Starlord) when he plays his tape recorder in the first scene shows the transition from diegetic sound to non-diegetic sound.

Sound bridge: A sound bridge is a type of frequency editing that happens when sound brings over a visual transition in a film. I.e, music might continue through a scene change or throughout as well as montage sequence to connect the scenes together in a creative and thematic way. 

Asynchronous sound: Asynchronous sound is a term for sound that has not been synchronized with the screen image. Also Asynchronous sound also includes aesthetic use of sound for expressive purposes. Because of the composite nature of film art, the element of sound (music, dialogue, sound effects) is highly manipulative. The sounds of a clucking chicken can be juxtaposed with a shot of a ranting politician for satirical effect. For instance from Hitchcock’s ‘The 39 steps’ (1935), asynchronous sound is used when you. see a woman screaming which then cuts to a steam train coming out of a tunnel.

Synchronous sound: Is sound that is matched with the action and movements being shown. An example portrays a character playing the piano, and the viewer hears the sounds of the piano simultaneously. An example in the film ‘The pianist’ (2002) Adrien Brody who plays (Władysław Szpilman) finishes up a piece in front of a German guard.