Immigration to the United States refers to the process by which individuals from other countries move to the U.S. to live, work, or study. This process can involve obtaining various types of visas, such as work visas, student visas, or family reunification visas. The U.S. has a long history of immigration, with people coming from diverse backgrounds and cultures. The U.S. government regulates immigration through laws and policies that determine who can enter the country and under what conditions. Organizations like the U.S. Citizenship and Immigration Services (USCIS) oversee the application processes, while the Department of Homeland Security (DHS) ensures national security related to immigration.