The document discusses conventions that are commonly used in thriller films and their trailers. It explains that thrillers typically use tension, suspense, violence, dark environments, and dreary music to create an atmosphere of fear. Cinematography techniques like low-key lighting, shadows, and camera angles are employed to heighten tension, as is editing with quick cuts and changing perspectives. Sound design with unsettling music and effects also contributes to making the audience feel uncomfortable. Thriller trailers often employ text cards and an enigmatic structure to confuse viewers and maintain suspense.