H Visas Temporary Employment
H visas are temporary worker visas for persons who want to enter the United States for employment lasting a fixed period of time, and are not considered permanent or indefinite. Each of these visas requires the prospective employer to first file a petition with U.S. Citizenship and Immigration Services (USCIS).
A citizen of a foreign country who wishes to enter or remain in the United States and work must first obtain a visa or approval of change of status. An approved petition is required to apply for a work visa or change of status. There are many different types of H visas and as a result different requirements.
The position requirements and your qualifications are the facts that determine what type of visa/status will fit better your circumstances.
Each H visa has different application requirements. Work visa application can be submitted for some work visa types three (3) and for some visas six (6) months in advance of the requested employment start date.