E-Verify is a United States Department of Homeland Security (DHS) website that allows businesses to determine the eligibility of their employees, both U.S. and foreign citizens, to work in the United States. The site was originally established in 1996 as the Basic Pilot Program to prevent companies from hiring people who had violated immigration laws and entered the United States unlawfully. In August 2007, the DHS started requiring all federal contractors and vendors to use E-Verify. The Internet-based program is free and maintained by the United States government. While federal law does not mandate use of E-Verify for non-federal employees, some states have mandated use of E-Verify or similar programs, while others have discouraged the program.