This text is an excerpt from the book American Government 101, which provides a comprehensive overview of the United States government. It covers various topics such as the origins of the Constitution, the structure and function of the three branches of government, political parties, elections, interest groups, and the role of the media in American politics. The excerpt focuses specifically on the legislative branch (Congress), the executive branch (the presidency), and the judicial branch (the Supreme Court), explaining their respective roles and powers. It also explores the relationship between the federal government and state governments, as well as the functions of local governments.