The President is both the head of state and head of government of the United States of America, and Commander-in-Chief of the armed forces.

Under Article II of the Constitution, the President is responsible for the execution and enforcement of the laws created by Congress. Fifteen executive departments — each led by an appointed member of the President's Cabinet — carry out the day-to-day administration of the federal government. They are joined in this by other executive agencies such as the CIA and Environmental Protection Agency, the heads of which are not part of the Cabinet, but who are under the full authority of the President. 

The President also appoints the heads of more than 50 independent federal commissions, such as the Federal Reserve Board or the Securities and Exchange Commission, as well as federal judges, ambassadors, and other federal offices. The Executive Office of the President (EOP) consists of the immediate staff to the President, along with entities such as the Office of Management and Budget and the Office of the United States Trade Representative.

The President has the power either to sign legislation into law or to veto bills enacted by Congress, although Congress may override a veto with a two-thirds vote of both houses. The Executive Branch conducts diplomacy with other nations, and the President has the power to negotiate and sign treaties, which also must be ratified by two-thirds of the Senate. 

The President can issue executive orders, which direct executive officers or clarify and further existing laws. The President also has unlimited power to extend pardons and clemencies for federal crimes, except in cases of impeachment.

With these powers come several responsibilities, among them a constitutional requirement to "from time to time give to the Congress Information of the State of the Union, and recommend to their Consideration such Measures as he shall judge necessary and expedient." Although the President may fulfill this requirement in any way he or she chooses, Presidents have traditionally given a State of the Union address to a joint session of Congress each January (except in inaugural years) outlining their agenda for the coming year.

The Constitution lists only three qualifications for the Presidency — the President must be 35 years of age, be a natural born citizen, and must have lived in the United States for at least 14 years. And though millions of Americans vote in a presidential election every four years, the President is not, in fact, directly elected by the people. Instead, on the first Tuesday in November of every fourth year, the people elect the members of the Electoral College. Apportioned by population to the 50 states — one for each member of their congressional delegation (with the District of Columbia receiving 3 votes) — these Electors then cast the votes for President. There are currently 538 electors in the Electoral College.

By tradition, the President and the First Family live in the White House in Washington, D.C., also the location of the President's Oval Office and the offices of the his senior staff. When the President travels by plane, his aircraft is designated Air Force One; he may also use a Marine Corps helicopter, known as Marine One while the President is on board. For ground travel, the President uses an armored Presidential limousine.