1. The document traces the historical trajectory of media effects research through four phases: from viewing media as all-powerful, to its effects being challenged, to powerful media being revisited, to negotiating how audiences make meaning from media. 2. Across these phases, research approaches and theories have shifted from behaviorism and conditioning, to cultivation analysis and social learning theory, to examining how audiences actively interpret media rather than being passive receivers. 3. A key challenge is that it is difficult to isolate the specific influence of media from other variables on behaviors, and research approaches each have their limitations such as lack of external validity or real-world application.