Codes refer to signs like images and sounds that work together to create meaning in media. There are three main categories of codes: visual codes involving color, images, costumes; auditory codes using sound; and technical codes covering production elements like framing, lighting, editing, and effects. Visual codes include color connotations and how positioning of objects creates meaning, like with traffic lights. Auditory codes contribute to meaning through sound. Technical codes cover physical production decisions that shape the meaning of media texts.