The Constitution of the US was created by the Founding Fathers to be the document on which the federal government is based. It was ratified in 1788 immediately after its creation. The Constitution begins with a section called the Preamble, which is followed by a number of articles and amendments. One of the key provisions in Article II of the Constitution states that a person who wishes to become president must have been born in the US and be at least thirty-five years of age. He or she must give a state of the union address from time to time and can only serve two four-year terms in office. The legislative branch of the federal government is made up of the US Congress. Its duties and responsibilities are spelled out in Article I of the Constitution. The judicial branch, which interprets the laws, is established by Article III of the Constitution. The Constitution is the most important legal document in the United States. It is also considered by many historians to be one of the most influential documents ever written.