The document provides definitions and explanations of several audience and media theories: The hypodermic needle theory from the 1920s-1930s viewed audiences as passive and unable to resist media messages. The two-step flow theory from the 1940s-1950s found that opinion leaders influence the masses by interpreting media for others. Uses and gratification theory explains that individuals use media for diversion, relationships, identity, and information. The document gives examples of how these theories apply to discussing and sharing a TV show and relating to a song's lyrics about relationships.