The Constitution of the United States is the supreme law of the United States of America. The Constitution, originally comprising seven articles, delineates the national frame of government.
Its first three articles embody the doctrine of the separation of powers, whereby the federal government is divided into three branches: the legislative, consisting of the bicameral Congress (Article I); the executive, consisting of the president (Article II); and the judicial, consisting of the Supreme Court and other federal courts (Article III).
Article IV, Article V and Article VI embody concepts of federalism, describing the rights and responsibilities of state governments, the states in relationship to the federal government, and the shared process of constitutional amendment.
Article VII establishes the procedure subsequently used by the thirteen States to ratify it. It is regarded as the oldest written and codified national constitution in force.