To visit the United States, you generally need a visa unless you're from a visa-exempt country (e.g., via the Visa Waiver Program for tourism or business visits of 90 days or less). Common types of U.S. visas include: B1/B2 Tourist Visa: For tourism, visiting family/friends, or attending business meetings. ESTA (Electronic System for Travel Authorization): For citizens of Visa Waiver Program countries, allowing stays of up to 90 days for tourism or business. F-1 Student Visa: For students enrolled in academic programs. H-1B Work Visa: For specialized workers in a U.S. company. J-1 Exchange Visitor Visa: For educational and cultural exchange programs. Visa applications typically require an online form, a visa interview, and biometric information. Processing times and fees vary, so check the U.S. Department of State website for details.