The United States of America is a federal constitutional republic comprising fifty states and a federal district. The country is situated mostly in central North America, where its forty-eight contiguous states and Washington, D.C., the capital district, lie between the Pacific and Atlantic Oceans, bordered by Canada to the north and Mexico to the south.

The United States population is projected by the U.S. Census Bureau to be 309,395,000, including an estimated 11.2 million illegal immigrants. The third most populous nation in the world, after China and India, the United States is the only industrialized nation in which large population increases are projected.

The United States is a multicultural nation, home to a wide variety of ethnic groups, traditions, and values. Aside from the now small Native American and Native Hawaiian populations, nearly all Americans or their ancestors immigrated within the past five centuries.

Sports in the United States are an important part of the United States culture. However, the sporting culture of the U.S. is different from that of many other countries. Compared to any other nation, Americans prefer a unique set of sports. For example, soccer, the most popular sport in the world, is not as popular in the U.S. compared to the four most popular team sports — namely baseball, American football, basketball, and ice hockey.