The document discusses different types of sounds used in film and TV production including diegetic and non-diegetic sounds. Diegetic sounds originate from within the story world while non-diegetic sounds do not. Selective sounds are used to emphasize key elements while ambient sounds create atmosphere. Sound bridges help transitions between scenes flow better. Voiceovers, music and effects are examples of non-diegetic sounds that do not originate from the story world. Silence is sometimes used provoke audience reaction.