<Tr> <Td> <Ul> <Li> </Li> <Li> </Li> <Li> </Li> </Ul> </Td> </Tr> <Ul> <Li> </Li> <Li> </Li> <Li> </Li> </Ul> <P> The United States Constitution is the supreme law of the United States . 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; the executive, consisting of the President; and the judicial, consisting of the Supreme Court and other federal courts . Articles Four, Five and Six embody concepts of federalism, describing the rights and responsibilities of state governments and of the states in relationship to the federal government . Article Seven 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 . </P> <P> Since the Constitution came into force in 1789, it has been amended 27 times, including an amendment to repeal a previous one, in order to meet the changing needs of a nation that has profoundly changed since the eighteenth century . In general, the first ten amendments, known collectively as the Bill of Rights, offer specific protections of individual liberty and justice and place restrictions on the powers of government . The majority of the seventeen later amendments expand individual civil rights protections . Others address issues related to federal authority or modify government processes and procedures . Amendments to the United States Constitution, unlike ones made to many constitutions worldwide, are appended to the document . All four pages of the original U.S. Constitution are written on parchment . </P>

The term used to refer to the official approval of the constitution by the states