I-94 Card Or “Arrival/Departure” Document

(As a non U.S. citizen) The I-94 form is the most important document indicating your entry to the US and is required for your legal stay in this country.

The I-94 Form is a white-colored form that will be given to non-US citizens in the airplane together with the US customs form.

Please make sure that this form is filled out correctlyand is consistent with your personal information in your passport. It is critical to spell your first name and last name exactly as it appears in your passport. Please pay special attention to space and dash characters.

At the port of US entry this card will be stamped by an immigration officer and the lower part will be stapled to your passport. Make sure that you have the correct notation on the stamp which is :
“F-1 D/S” for F-1 visa holder and “J-1 D/S” for J-1
visa holder.
D/S stands for Duration of Status.
Always carry your I-94 card

You must have your I-94 card with you for all travel, even travel within the United States.

Here is a sample of I-94 form

HERE