A visa is a conditional authorization granted by a country to a foreigner that allows them to enter, remain within, or leave its territory. A visa is obtained at a countrys embassy or consulate abroad and is placed in the travelers passport. A visitor visa is a type of nonimmigrant visa for persons who want to enter a country temporarily for business, tourism, or a combination of both purposes. The type of visa requested should match the purpose of the visit, and visa types are classified using an alpha-numeric system.

An entry visa is a type of visa that permits the bearer to cross the border and enter the country of issue just once. It is not an actual visa, but rather permission to allow the traveler to enter a specific country. Entry visas can be issued for pre-approval purposes or for specific purposes. Some countries require an entry visa in addition to a tourist visa, while others only have multiple-entry visas.

It is important to note that a visa does not guarantee entry into a country, as the Department of Homeland Security officials at the port-of-entry have the authority to permit or deny admission to the country.