The B non-immigrant visa category covers foreign visitors for business (B-1) and pleasure (B-2).
F Visa (Student Visa) / Optional Practical Training
F visas are for full-time students in a degree program. When a student is in a bachelor’s, master’s, or doctoral program and has completed all course requirements for the degree, he or she is eligible for a 12 month period of OPT or Optional Practical Training.
J visas cover exchange visitors, such as students, scholars, and au pairs. J-1 students are eligible for academic training after graduation. Academic training provides an opportunity to apply theoretical knowledge obtained in an academic program to a practical work experience. Doctoral students who obtain a post-doc position may be eligible for academic training. Employment must be authorized by the Responsible Officer at the academic institution.
The H-1B visa program is intended to permit US employers to hire the highly educated employees for “specialty occupations” (positions that require at least a Bachelor’s Degree in a specialized field). Examples include Research Associates, engineers, accountants, medical personnel, and computer professionals. The period of stay for H-1B holder is 6 years, and an application must be made to USCIS. Extensions beyond six (6) years may be possible under certain circumstances.
O and P Visa
Foreign nationals who have demonstrated extraordinary ability in the sciences, arts, education, business or athletics may be able to receive an O visa to work in their area of expertise. By way of example, an art school graduate with an exceptional portfolio might be eligible for an O visa. The period of stay for an O visa is 3 years and incremental extensions are available. P visas are available for performing artists and athletes. These visas require applications to USCIS.
TN visas are similar to H-1B visas, but they are available only to Canadian and Mexican nationals, and cover a limited number of job titles.
R visas are for religious workers. The workers must be performing a religious function, such as a Minister or Music Director.