The citizens residing in the countries that allow VWP (Visa Waiver Program) are eligible for applying an ESTA for the purpose of business travel of tourism and are limited to a period of ninety days for the stay. All individual traveling with Electronic System for Travel Authorization must have a valid reason for traveling and must hold a valid citizenship from a VWP (Visa Waiver Program) country.
The citizens of a Visa Waiver Program (VWP) country are permitted to travel internationally even if they do not possess a valid passport but must pass all the rules and regulations that are subjected to the ESTA program and must possess a valid approval prior to the travel o the country that they desire. There is an automatic response that is provided by the system and generated within a short span of time, on approval, an electronic verification is conducted before boarding with the customs officials in order to check the validity and verify the eligibility for traveling. A visa permits an individual to travel to the countries even for the same reason again for which the visa was initially issued. In case an individual holds a valid visa, they do not need to get hold of an ESTA 申請 or even apply for an Electronic System for Travel Authorization. The norms related to Electronic System for Travel Authorization signify that there is no need to apply for the ESTA again and again in the span of the two permitted years of validity for multiple visits internationally.
An ESTA does not permit an individual to stay in the country for a span of two years at a stretch; it only allows an individual to travel to the country for a specific reason from countries under the VWP (Visa Waiver Program) for a maximum time-span of ninety days at a maximum.