The United States has a constitutional federal republic form of government, which operates under principles of democracy. It is a system where power is divided between a national (federal) government and individual state governments. The federal government itself is composed of three branches: the legislative (Congress), the executive (headed by the President), and the judicial (Supreme Court and other courts). This structure ensures a separation of powers and checks and balances among branches. Citizens elect representatives to make decisions on their behalf, making it a representative democracy as well.