UNITED STATES IMMIGRATION VISAS
B-1 visa may not be compensated by a U.S. entity for work performed during their visit. Any compensation for such work must be paid by a foreign entity. They may be reimbursed by the U.S. entity for incidental or out of pocket expenses.
B-2 visa holders may apply for an extension and if approved, the extension may not exceed six months.
F1 visa is valid for as long as it takes the student to finish his or her course of study. F-1 visas allow students to work on campus, and off campus in some situations. Upon completion of their academic programs, F1 visa holders are eligible to apply for employment authorized practical training. F-1 visas will not grant a permanent residency in the United States, and students must leave the United States within 36 days once the course of study or practical training has been completed.
H-1B visa process. In fact, the entire H-1B visa process is out of the hands of employees. Another important thing to keep in mind about the H-1B visa is that there are many requirements involved in getting one.
H2A visa is valid up to one year, and may be renewed annually up to a maximum of three years. An agricultural worker who has held an H-2A nonimmigrant status for three years is required to leave the United States, and remain outside for three consecutive months prior to seeking readmission in the United States under H-2A.