SEVIS I-20 (Certificate of Eligibility for Nonimmigrant (F-1) Students):
This form is required in order to obtain F-1 status. The form is issued by the school to fully admitted, degree-seeking students who have shown sufficient funds to cover their studies in the U.S.

Passport: A document issued by a government to identify a person as a citizen of a particular country and allow the bearer to travel abroad and permit re-entry to the home country. The visa is stamped on the passport. U.S. immigration law requires that non-immigrants possess valid passport to enter the U.S. and that passport remain valid through the time that the bearer is in the U.S.

B-2 Visa: The stamp issued by a U.S. consular post abroad allowing the bearer to enter the U.S. as a Tourist. The principal activity in this case is for pleasure (i.e. tour the U.S. on a vacation).

F-1 Visa: The stamp issued by a U.S. consular post abroad allowing the bearer to enter the U.S. as a student on F-1 status. An F-1 visa is an entry permit and cannot be "extended" in the U.S. since F-1 visas can only be obtained or renewed at a U.S. consular post abroad.

Form I-94 (Arrival/Departure Record): Form used by U.S. Customs and Border Protection (USCBP) to document entry to and departure from the U.S. of all foreigners. At entry, this form is stamped according to the bearer's visa classification. The date or period through which the bearer is authorized to remain in the U.S. is also noted on this form. An Admission Number is a unique 11-digit number found on the I-94 used by USCBP to document entries and exits from the U.S.