The H-1B is a non-immigrant visa in the United States under the Immigration and Nationality Act, section 101(a)(15)(H). It allows U.S. employers to temporarily employ foreign workers in specialty occupations. If a foreign worker in H-1B status quits or is dismissed from the sponsoring employer, the worker can apply for a change of status to another non-immigrant status, find another employer (subject to application for adjustment of status and/or change of visa), or must leave the US.
The regulations define a “specialty occupation” as requiring theoretical and practical application of a body of highly specialized knowledge in a field of human endeavor including, but not limited to, architecture, engineering, mathematics, physical sciences, social sciences, biotechnology, medicine and health, education, law, accounting, business specialties, theology, and the arts, and requiring the attainment of a bachelor’s degree or its equivalent as a minimum (with the exception of fashion models, who must be "of distinguished merit and ability".) Likewise, the foreign worker must possess at least a bachelor’s degree or its equivalent and state licensure, if required to practice in that field. H-1B work-authorization is strictly limited to employment by the sponsoring employer.