The F-1 i.e. Academic Student Visa allows an individual to enter the United States as a full-time student at an accredited college, university, seminary, conservatory, academic high school, elementary school, other academic institution or in a language training program. One must be enrolled in a program of study that leads up in a certificate, degree, or diploma, and the relevant institution must be authorized to accept international students by the U.S. government.
The M-1 visa i.e. Vocational Student Visa category includes students in vocational or other nonacademic programs, other than language training.
In regards to the employment, students who are on F-1 VISA may not be eligible to work off-campus during the first academic year, however, he/ she may be able to accept on-campus employment subject to certain conditions or restrictions. In addition, students under F-1 visa may also be eligible to work off-campus (decided on a case-by-case basis) in case special circumstances such as a severe economic hardship is to arise or let’s say a special student relief is needed. Student under M-1 VISA, however, may engage in practical training only after they have completed their studies.
For both F-1 and M-1 students; any off-campus training or employment must be directly related to their area or subject of study and must be authorized prior to starting any work by the Designated School Official (i.e. the person authorized to maintain the Student and Exchange Visitor Information System (SEVIS) and USCIS (United States Citizenship and Immigration Services). Now, only noncitizens who have permission from DHS (Department of Homeland Security) to work can apply for a Social Security number.
After the first academic year, students under F-1 VISA will have the chance to engage in any of these three types of off-campus employment of which the OPT are generally of 24 months;
• Curricular Practical Training (CPT)
• Optional Practical Training (OPT) (pre-completion or post-completion)
• Science, Technology, Engineering, and Mathematics (STEM) Optional Practical Training Extension (OPT)

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