Introduction

The United States, officially known as the United States of America, is located in North America and is a federal country composed of 50 states and 1 federal district (the capital). It borders the Atlantic Ocean to the east, the Pacific Ocean to the west, Canada to the north, and Mexico and the Caribbean Sea to the south. The United States is the fourth-largest country in the world, after Russia, Canada, and China.

Geographically, the terrain of the United States is extremely diverse, ranging from the Atlantic coastal plains in the east to the Central Great Plains in the middle, and then to the Rocky Mountains and the Pacific coastal areas in the west, with rich landform changes. The natural landscapes of the United States include majestic mountains, vast forests, fertile farmlands, and extensive deserts. In addition, the United States has numerous rivers and lakes, among which the Mississippi River and the Columbia River are the most famous.

Culturally, the United States is an immigrant country that has brought together people from all over the world. Therefore, American culture is very diverse, integrating the characteristics of various ethnic groups, religions, and languages. The official language of the United States is English, but Spanish and other languages are also very common in some regions. The education system in the United States is well-developed, with many world-renowned universities and research institutions.

In terms of population, the United States is the third most populous country in the world, with a population of over 300 million according to the latest statistics. The population distribution is uneven, with coastal cities and southern regions being more densely populated, while the Midwest and rural areas have relatively fewer people. The population structure of the United States is also constantly changing, and immigration has an important impact on the population growth and cultural diversity of the United States.

Administratively, the United States is composed of 50 states, 1 capital (Washington, D.C.), and some overseas territories. Each state has its own state government and legislative body, responsible for internal affairs of the state. Washington, D.C. is the capital of the United States and the seat of the U.S. federal government.