The document discusses interest groups and political action committees (PACs) in the United States. It provides background on the growth of interest groups and reasons for their proliferation, including economic developments, government agencies, and technology. Various types of interest groups are described such as traditional economic groups, public interest groups, and ideological groups. Tactics used by interest groups like lobbying, campaign contributions, and media are also summarized. The rise of PACs is covered, explaining how they raise funds for candidates within certain contribution limits.