Currently citizens of thirty-seven (37) countries qualify for the Visa Waiver Program which allows after approval. The non-US Citizen applicant must be in possession if a machine readable passport that is valid for at least six (6) months after the date of departure.
The VWP countries are: Andorra, Australia, Austria, Belgium, Brunei, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Iceland, Hungary, Ireland, Italy, Japan, Latvia, Liechtenstein, Lithuania, Luxembourg, Malta, Monaco, the Netherlands, New Zealand, Norway, Portugal, San Marino, Singapore, Slovenia, Slovakia, South Korea Spain, Sweden, Switzerland, Taiwan and the United Kingdom.
VWP travellers who have valid machine-readable passports with a digital photo that were issued before October 26, 2006 do not need an e-Passport until their current valid passport expires. To check if your passport meets the VWP requirements, check https://visaguide.world/us-visa/nonimmigrant/visitor/visa-waiver-program/.
Citizens of the Czech Republic, Estonia, Greece, Hungary, Latvia, Lithuania, Malta, the Republic of Korea, and the Slovak Republic must have a machine readable passport with an integrated chip containing information from the passport data page = e-Passport. Citizens of Taiwan must have a machine readable passport with an integrated chip from the passport data page = e-Passport as well as a national identity number.
The e-Passports may be identified by the international e-Passport symbol on the cover. They are equipped with an electronic chip that stores the bearer’s biographic information and digital photo. The U.S. started issuance of e-Passports in 2006.
In order to travel without a visa on the VWP, you must have authorization through the Electronic System for Travel Authorization (ESTA) prior to boarding a U.S. bound air or sea carrier. ESTA is the Department of Homeland Security, Customs and Border Protection's (CBP) automated web-based system to determine eligibility to travel without a visa to the United States for tourism or business.
Some countries do not issue machine readable passports and therefore their citizens cannot apply for the VWP. In any event, visa applications can be made for B Visas – B-1 for Business Visitors and B2 for Visitors for Pleasure, if so desired.
For more detailed information regarding the VWP, check one of these links:
https://visaguide.world/us-visa/nonimmigrant/visitor/visa-waiver-program/
http://cbp.gov/xp/cgov/travel/id_visa/esta/
http://www.cbp.gov/xp/cgov/travel/id_visa/business_pleasure/vwp/faq_vwp.xml