The document discusses several theories about how media influences the public:
1) The hypodermic needle theory suggests that media has a direct and powerful effect on audiences and people cannot escape its influence.
2) Uses and gratification theory proposes that people seek out specific media to fulfill needs like diversion, relationships, identity, and surveillance.
3) Passive and active consumption theory holds that even passive viewers are influenced by media messages, though active audiences question and interpret messages.
The document analyzes how music videos can influence viewers' purchasing behaviors and fulfill psychological needs through both passive and active consumption.