ESTA or visa?
The Visa Waiver Program lets citizens of participating countries visit the United States for 90 days or less without a visa. They need an approved ESTA before they travel and an e-passport.
If your country is not in the programme, if you plan to stay longer than 90 days, or if you are not eligible for ESTA, you apply for a B-1/B-2 visitor visa.
U.S. Department of State: Visa Waiver Program
