Hungary is a member of the Visa Waiver Program (VWP), which enables citizens of participating countries to travel to the United States for tourism or business for 90 days or less without obtaining a U.S. visa. Visitors applying for entry under this program are allowed to remain for a maximum of 90 days. Travelers must meet certain requirements and have a valid Electronic System for Travel Authorization (ESTA) approval prior to travel.
Visitors who enter on the VWP cannot change status or extend their duration of stay. Travelers coming to the United States under the VWP cannot work or study. If you plan to stay for more than 90 days, or if you intend to study or to work, you MUST obtain a visa before traveling. Overstay consequences are severe; make sure you know the rules before you travel! You can find more information at the websites of the Department of Homeland Security and the Department of State.
More About the Visa Waiver Program (VWP)
How to Obtain a Tourist Visa
Travel Tips (Security Screening, What Can I Bring, etc.)