If you wish to visit the United States temporarily or be granted entry for a very specific period of time, you will need a non-immigrant visa. The purpose of your trip will determine which visa you should apply for. If you plan to take a vacation, or visit family and friends, a B-2 visa is appropriate. If you have business undertakings, a B-1 visa may be your best option. No visa is required for citizens of the 39 countries that are part of the Visa Waiver Program (VWP), if a single stay will be no longer than 90 days. Canadians and Bermudians are also allowed entry, without a visa, or up to 6 months.