There are fifty states and one federal district which make up the United States of America. The United States of America is a constitutional federal republic and the major portion of it is situated in the centre of North America. That is where Washington, D.C, which is the capital district, and forty eight of its contiguous states lie. These are positioned in the middle of the Atlantic Ocean and the Pacific Ocean and are surrounded by Mexico and Canada on the south and the north respectively. On the north west of the United States of America is the state of Alaska. Russia is located on the west across the Bering Strait, Canada is on its east, and the state of Hawaii, which is an archipelago, is situated in the middle of the Pacific Ocean. There are a number of insular areas and territories which are a part of the United States of America, and they are spread around the Pacific Ocean and the Caribbean.
The United States of America cover an area of around 9.83 million square kilometers, and are home to more than three hundred million people. With respect to total area, it ranks fourth among all the countries of the world. And with respect to land area it ranks third, as well as by population. Because of the large scale of people who migrate to United States of America from other countries of the world, its regions are the most ethnically diverse when compared to any other country in the world. The national economy of the country is the largest of the world. The gross domestic product of the year 2006 amounted to more than thirteen trillion U.S dollars.
The United States Declaration of Independence was issued on July 4 in the year 1776. This declared that the United States of America was a separate country and wanted to be separate Great Britain, which had colonized the region. The American Revolutionary War was fought and the British were defeated.