Public Opinion is a comprehensive and multidisciplinary examination of public opinion in the United States. Drawing on scholarship in political science, psychology, sociology, and communications, the authors explore the nature of political and social attitudes in the United States and how these attitudes are shaped by various institutions, with an emphasis on mass media. The book also serves as a provocative starting point for the discussion of citizen moods, political participation, and voting behavior. The book now contains two revised and reframed theory chapters—“Group Membership and Public Opinion” and “Public Opinion and Social Process”—as well as new coverage of the influence of online and social media on public opinion, especially in issue opinions and campaigns.