what is esta travel authorization
ESTA is an automated system that determines the eligibility of visitors to travel to the U.S. under the Visa Waiver Program (VWP). Authorization via ESTA does not determine whether a traveler is admissible to the United States.n addition, a traveler must obtain a new ESTA authorization if any answer to the ESTA application eligibility questions changes. Entry under the Visa Waiver Program is only valid for a combined maximum stay in the USA and its surrounding countries of ninety days.