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. Visitor visas are nonimmigrant visas for persons who want to enter the United States temporarily for business (visa category B-1), tourism, pleasure or visiting (visa category B-2), or a combination of both purposes (B-1/B-2).
B-1: Temporary Business Visitor
You may be eligible for a B-1 visitor visa if you will be participating in business activities of a commercial or professional nature in the United States. If you are in the United States in another valid nonimmigrant status, you may be eligible to change to B-1 status.
B-2: Temporary Tourist Visitor
If the purpose of the planned travel is recreational in nature, including tourism, visiting friends or relatives, rest, or is related to medical treatment, activities of a fraternal, social, or service nature, or participation by amateurs who will receive no remuneration in musical, sports and similar events or contests, then a visitor visa (B-2) would be the appropriate type of visa for the travel. Persons planning to travel to the United States for a different purpose including students, temporary workers, crew members, or journalists, must apply for a different category of visa.
Visa Waiver Program
The Visa Waiver Program (VWP) enables nationals of 35 participating countries to travel to the United States for tourism or business for stays of 90 days or less without obtaining a visa. Nationals of VWP countries must meet eligibility requirements to travel without a visa on the VWP. VWP travelers are required to have a valid authorization through the Electronic System for Travel Authorization (ESTA) prior to travel.
K-1: Fiancé VIsa
The K-visa categories for fiancé(e)s of U.S. citizens and their accompanying minor children (K-1 and K-2 visas) were created so fiancé(e)s can be spared a long separation from their intended spouse. Upon entry to the U.S., fiancé(e)s must marry their U.S. citizen spouse within 90 days and file for adjustment of status in order to get your green card and to remain legally in the United States.