The Visa Waiver Program allows foreign nationals from certain countries to travel to the United States for business or pleasure, for stays of 90 days or less without obtaining a visa. Travelers admitted under the Visa Waiver Program must agree to waive their rights to review or appeal, as explained in the Waiver of Rights section of the Application screen. See Who is eligible to apply for admission under the Visa Waiver Program? for further information.
For further information refer to § 217 of the Immigration and Nationality Act, 8 U.S.C. § 1187, and 8 C.F.R. § 217.