The foundational laws and principles of the United States are outlined in the Constitution. Ratified in 1788, it establishes the structure of the federal government and delineates the rights of citizens. The Constitution comprises a preamble, seven articles, and 27 amendments. It addresses the powers of the three branches of government: the Legislative, Executive, and Judicial. The first ten amendments constitute the Bill of Rights, protecting individual liberties. The Constitution serves as the supreme law of the land, guiding the operation of the U.S. government and the rights of its citizens.