This document discusses different types of sound and editing techniques used in films. It explains that diegetic sound originates from within the film's world, like voices and objects, while non-diegetic sound does not, like added music or effects. It describes several editing techniques like cuts, dissolves, fades, and montage. Cuts rapidly transition between scenes while dissolves and fades suggest more time has passed. Montage compresses time through fast-paced juxtaposition of shots.