The Constitution of the United States of America is the supreme law of the United States. It provides the framework for the organization of the United States Government. The document defines the three main branches of the government: The legislative branch with a bicameral Congress, an executive branch led by the President, and a judicial branch headed by the Supreme Court. Besides providing for the organization of these branches, the Constitution carefully outlines which powers each branch may exercise. It is the shortest and oldest written constitution of any major sovereign state.