The important document that established the framework for the government of the United States is the Constitution, ratified in 1788. The Constitution outlines the structure, functions, and powers of the federal government and serves as the supreme law of the land. It consists of a preamble and seven articles covering various aspects of governance, including the separation of powers among the legislative, executive, and judicial branches. Additionally, the Constitution has been amended several times, with the Bill of Rights—the first ten amendments—ensuring individual liberties and limiting governmental power to protect citizens' rights.