In every case, you must fill out the DS-160 form.
For a student visa (F-1 or M-1), you will need the I-20 form processed by the American school or institution you will be attending.
If you have a J-1 visa to study, you will need the DS-2019 form, issued by your program sponsor. If you are coming as a J-1 intern or trainee, you will additionally need the DS-7002 form as well.
Some work visas require additional forms. H-1B and O-1 visa applications, for example, include a form called I-129.
Does this sound super complicated? Don't worry! We will help you process forms to obtain your tourist and/or student visa.