US

For alternative meanings, see the disambiguation page for US, USA, United States, or American.

United States of America

Flag Coat of Arms
Motto: E pluribus unum (1789 to present) (Latin: "Out of Many, One") In God We Trust (1956 to present)
Anthem: The Star-Spangled Banner
Capital	Washington, D.C. 38°53′ N 77°02′ W
Largest city	New York City
Official languages	None at federal level; English de facto
Government  • President  • Vice President	Federal republic George W. Bush (R) Dick Cheney (R)
Independence  • Declared  • Recognized Constitution  • Completed  • Ratified  • Effective	From Great Britain July 4, 1776 September 3, 1783 September 17, 1787 May 23, 1788 March 4, 1789
Area  • Total  • Water (%)	9,631,418 km² (3rd) 4.87%
Population  • 2005 est.  • 2000 census  • Density	297,700,000 (3rd) 281,421,906 32/km² (140th)
GDP (PPP)  • Total  • Per capita	2005 estimate $12,589,600 million (1st) $42,367 (2nd)
HDI (2003)	0.944 (10th) – high
Currency	Dollar ($) (USD)
Time zone  • Summer (DST)	(UTC-5 to -10) (UTC-4 to -10)
Internet TLD	.us .gov .edu .mil .um
Calling code	+1

The United States of America is a country situated primarily in North America. It comprises 50 states and one federal district, and has several territories. It is also referred to, with varying formality, as the United States, the U.S., the U.S.A., the States, America, or (poetically) Columbia.

Since the mid-20th century, following World War II, the United States has emerged as a dominant global influence in economic, political, military, scientific, technological, and cultural affairs. Because of its influence, the U.S. is considered a superpower and, particularly after the Cold War, a hyperpower by some.

The country celebrates its founding date as July 4, 1776, when the Second Continental Congress — representing thirteen British colonies — adopted the Declaration of Independence that rejected British authority in favor of self-determination. However, the structure of the government was profoundly changed in 1789, when the states replaced the Articles of Confederation with the United States Constitution. The date on which each of the fifty states adopted the Constitution is typically regarded as the date that state "entered the Union" to become part of the United States.