The Constitution of the United States is the supreme law of the United States of America. It is the framework for the organization of the United States government and for the relationship of the federal government with the states, citizens, and all people within the United States.
The first three Articles of the Constitution establish the three branches of the national government: a legislature, the bicameral Congress; an executive branch led by the President; and a judicial branch headed by the Supreme Court. They also specify the powers and duties of each branch. All powers not enumerated are reserved to the respective states and the people, thereby establishing the federal system of government.
The Constitution was adopted on September 17, 1787, by the Constitutional Convention in Philadelphia, Pennsylvania, and ratified by conventions in each U.S. state in the name of "The People". It has been amended twenty-seven times; the first ten amendments are known as the Bill of Rights.The United States Constitution is the oldest written constitution (when defined as a single document) still in use by any nation in the world. Parts of San Marino's Constitution are older, dating to the 1600s. It holds a central place in United States law and political culture. The handwritten original document penned by Jacob Shallus is on display at the National Archives and Records Administration in Washington, D.C.