The United States of America (also referred to as the United States, the U.S., the USA, or America) is a federal constitutional republic comprising fifty states and a federal district. Central North America is where most of the States are situated. The 2 states that differ from this rule are Alaska and Hawaii. It is bordered by Canada and Mexico. The two oceans that also border the USA are The Pacific to the west and the Atlantic to the East (see map of the world. The Land Mass is approximately 3.79 million square miles which is approximately 9.7 million square kilometres. The United States is usually considered the 3rd largest country in the world after Russia and Canada, although this fact is being disputed. See here for more information about this Wikipedia – List of countries and outlying territories by total area.