Generally, a citizen of a foreign country who wishes to enter the United States must first obtain a visa, either a nonimmigrant visa for temporary stay or an immigrant visa for permanent residence. The visitor visa is a nonimmigrant visa for persons desiring to enter the United States temporarily for business (B-1) or for pleasure or medical treatment (B-2). Persons planning to travel to the U.S. for a different purpose, such as students, temporary workers, crewmen, journalists, etc, must apply for a different visa in the appropriate category. Travelers from certain eligible countries may also be able to visit the U.S. without a visa, through the Visa Waiver Program.
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