A visa is a grant of permission to enter the country. The USA entrance requirements are as follows:

There are three types of student visas:

Of these, the F-1 and the J-1 are the most common for international students.

If the foreign student advisor believes you have the resources necessary for study in the US, he or she will send you a Form I-20 (Certificate of Eligibility for Nonimmigrant [F-1] Student Status). You will need to submit this form with your application for a student visa to the American embassy or consulate. You will also have to provide proof of proficiency in English (unless you are enrolling in a language program). You will also need Form OF-156 (Non-Immigrant Visa form available from USA consular offices), a valid passport, a 1-1/2 inch square photograph (37 mm x 37 mm) showing full face against a light background, and the visa processing fee.