A B-1 visa is for temporary visitors who wish to engage in business activities, but not productive work, while in the U.S. A B-2 visa is for temporary visitors who wish to engage in personal activities, such as visiting family, shopping, and sightseeing. Citizens of certain countries are permitted to visit the U.S. without a visa through the Visa Waiver program. To enter on Visa Waiver, a visitor must first register on the ESTA site.