Overview
The United States of America (USA), often referred to simply as the United States (U.S.) or America, is a country located primarily in North America. It is organized as a federal republic composed of 50 states along with a federal capital district, Washington, D.C. With a population exceeding 341 million, the United States is the third-most populous country in the world, and it also ranks third globally in terms of land area, making it a megadiverse nation in terms of geography, ecosystems, and culture.
Geography
The United States spans a vast and varied landscape across North America. The 48 contiguous states share a northern border with Canada and a southern border with Mexico. In addition to these states, the country includes two geographically distinct regions:
- Alaska, a semi-exclave located in the northwest of the continent, separated from the contiguous states by Canadian territory.
- Hawaii, an archipelago situated in the Pacific Ocean, far from the North American mainland.
Beyond the 50 states, the United States asserts sovereignty over several island territories located in Oceania and the Caribbean, as well as various smaller, uninhabited islands scattered across these regions.
Government and Structure
As a federal republic, the United States divides governing authority between a national government and individual state governments. Each of the 50 states retains a degree of autonomy while remaining part of the larger union. Washington, D.C., functions as the federal capital district, serving as the seat of the national government but existing outside the boundaries of any individual state.
Population and Diversity
With a population surpassing 341 million people, the United States is home to a highly diverse society. This diversity is reflected not only in its population but also in its physical geography, which ranges from arctic conditions in Alaska to tropical climates in Hawaii, and from dense forests to arid deserts across the contiguous states. This combination of demographic and environmental variety contributes to the country's designation as megadiverse.
Territories
In addition to its core 50 states, the United States maintains political ties to five major island territories, extending its geopolitical presence into the Pacific and the Caribbean. These territories, along with numerous smaller islands, form part of the broader scope of U.S. sovereignty beyond the North American mainland.