The United States of America /əˈmɛrɪkə/ (USA), commonly known as the United States (U.S.) or America, is a constitutionalfederal republic composed of 50 states, a federal district, five major self-governing territories, and various possessions.[fn 6] Forty-eight of the fifty states and the federal district are contiguous and located in North America between Canada and Mexico. The state of Alaska is in the northwest corner of North America, bordered by Canada to the east and across the Bering Strait from Russia to the west. The state of Hawaii is an archipelago in the mid-Pacific Ocean. The U.S. territories are scattered about the Pacific Ocean and the Caribbean Sea. Nine time zones are covered. The geography, climate and wildlife of the country are extremely diverse.
At 3.8 million square miles (9.8 million km2) and with over 324 million people, the United States is the world’s third- or fourth-largest country by total area,[fn 7] third-largest by land area, and the third-most populous. It is one of the world’s most ethnically diverse and multicultural nations, and is home to the world’s largest immigrant population. The capital is Washington, D.C., and the largest city is New York City; nine other major metropolitan areas—each with at least 4.5 million inhabitants and the largest having more than 13 million people—are Los Angeles, Chicago, Dallas, Houston, Philadelphia, Miami, Atlanta, Boston, and San Francisco.
Paleo-Indians migrated from Asia to the North American mainland at least 15,000 years ago. European colonization began in the 16th century. The United States emerged from 13 British colonies along the East Coast. Numerous disputes between Great Britain and the colonies following the Seven Years’ War led to the American Revolution, which began in 1775. On July 4, 1776, during the course of the American Revolutionary War, the colonies unanimously adopted the Declaration of Independence. The war ended in 1783 with recognition of the independence of the United States by Great Britain, representing the first successful war of independence against a European power. The current constitution was adopted in 1788, after the Articles of Confederation, adopted in 1781, were felt to have provided inadequate federal powers. The first ten amendments, collectively named the Bill of Rights, were ratified in 1791 and designed to guarantee many fundamental civil liberties.
Visa is required for all non-American citizens.
|Currency used||American dollar (USD)|
|Area (km2)||9,857,306 km2|