What is a Visa?

A visa is a stamp placed in your passport by a U.S. consulate or embassy outside of the U.S. All visas serve as U.S. entry documents. They can be designated as either nonimmigrant or immigrant. Nonimmigrant visas are for people with permanent residence outside the U.S., but who wish to be in the U.S. on a temporary basis. Immigrant visas are for those who intend to live permanently in the U.S.

Except for a few types of visa renewals, visas cannot be issued inside American borders. Thus, you must be outside the U.S. to obtain a visa.