Entering the United States, the one shall think about issuing a visa as one of the first steps. However, a Visa Waiver Program, valid on the territory of the United States since 1988, suspends the citizens of certain countries from the issuance of a U.S. visa for the business or tourism purposes for no longer than 90 days. The countries that are a part of the program are Australia, Andorra, Austria, Brunei, Belgium, Chile, Czech Republic, Denmark, Estonia, France, Finland, Germany, Greece, Hungary, Ireland, Iceland, Italy, Japan, Latvia, Luxembourg, Liechtenstein, Lithuania, Monaco, Malta, Netherlands, New Zealand, Norway, Portugal, San Marino, Slovakia, Slovenia, South Korea, Spain, Sweden, Singapore, Switzerland, Taiwan, United Kingdom.
To acquire that program's membership, the one shall acquire it online via the Electronic System for Authorization (ESTA). After the document is being issued, it will be valid for only two years and allow coming to the United States with specific purposes.
Notably, Canada, Cayman, Bermuda, Mexico, The Turks and Caicos Islands citizens may enter the United States without a visa.
Some regulations shall still be met by the citizens of those countries when entering the United States:
Bermudians and Canadians may enter the United States without a visa for no longer than six months only;
The limit a maximum of 90 days is applicable for those that enter the United States under a visa-free program;
Moreover, the citizens of the Marshall Islands, Palau, and the Federated States of Micronesia may come to the United States with the study or business purposes in case if they provide a valid passport or any other TSA-approved identification document.
There are two types of a visa valid on the territory of the United States: Immigrant Visa that might be obtained for the permanent stay in the United States, and Non-Immigrant Visa that might be acquired with the purpose of the temporary stay in the United States.
However, recently the citizens of Libya, Iran, Syria, Somalia, Venezuela, North Korea, and Yemen were suspended from the ability to receive a visa under the president-signed proclamation of Donald Trump dated of December 4th, 2017.