What is a fiancé(e) visa?
A fiancé(e) visa (or K-1 visa) is technically a nonimmigrant visa. Because the process is similar to that of an immigrant visa, however, the Immigrant Visa Unit of the U.S. Embassy in Tashkent handles fiancé(e) visas. The fiancé(e) visa is for foreigners who wish to marry a U.S. citizen in the United States and then become legal permanent residents without having to leave the United States. K-2 visas are for unmarried children under 21 years of age of K-1 applicants. K-2 applicants must be present for the interview.
You can learn more about fiancé(e) visas on usvisas.state.gov.