The "F" visa is for academic studies, and the "M" visa is for nonacademic or  vocational studies.

 Requirements
 Procedure
 (1) Get your passport made. Follow this link for detailed information regarding        how to obtain your passport.

 (2) Once an academic institute has accepted you for admission to full-time        study,they will send you a document known as the I-20 form, which is        extremely necessary for the application for a student visa. This form I-20        contains information about how much financial responsibility you will need,        what is going to be the duration of your studies, etc.

 (3) You may need to show the proof of financial support if you or your parents        are going to fund your studies in USA. A bank letter may be necessary.        You might want to find out from your embassy about the types of        documents they may accept regarding the proof of financial support.
       Get an "Affidavit of Support" form from the U.S. Embassy or Consulate if        the studies are going to be sponsored by your relatives or others who are        currently in USA. Complete this form with information about your sources        of financing (letter of sposorship), and submit it along with your other        documents. The embassy may require a letter from the bank that holds the        funds.

 (4) Obtain all the necessary documents mentioned on this page. Now, you are        ready to go to the U.S. Consulate for a visa interview. If your visa is
       rejected twice, you may need to apply by mail.

 Documents required for obtaining the visa
 A nonrefundable application fee (You should find out the exact amount before  going  to the consulate and carry exact change if possible).
 An application Form OF-156, completed and signed. Blank forms are
 available without charge at all U.S. consular offices.
 A passport valid for travel to the United States
 One photograph 1 and 1/2 inches square (37x37mm) for each applicant,
 showing  full face, without head covering, against a light background; and
 For the "F" applicant, a Form I-20A-B. For the "M" applicant, a Form I-20M-
 N.
 [These forms are sent by the institutions where you have applied and upon  acceptance they send you these forms.]
 Sponsorship letters
 Student visa applicants must establish to the satisfaction of the consular officer
 that  they have binding ties to a residence in a foreign country which they have
 no intention of abandoning, and that they will depart the United States when  they have completed their studies.

 Maintaing Visa Status After Arrival
 If a student on a F-1 visa is not able to complete their studies by the expiration  date  on the I-20 form, they must apply to the school's Foreign Student
 Advisor  for an  extension 30 days before expiration. Extensions are normally
 granted for  academic  and medical reasons so long as there have been no  violations of visa  status.
 It is possible to transfer schools after arrival on an F-1 visa. You will need to  notify  your current school of the transfer and obtain an I-20 form from the new  school.  You will complete the student certification section of the I-20 and must  deliver it to  the foreign student advisor at the new school within 15 days of  beginning attendance  at the new school.

 If you are changing majors at your current school, you do not need to notify the  INS. If you are changing degree programs (e.g., from a bachelors degree to a  masters degree program), however, you will need to get a new I-20 and submit
  it to the foreign student advisor within 15 days of beginning the new program.