SEVIS stands for Student and Exchange Visitor Information System.
It is a system that the US Department of State and Homeland Security keep track of all participants on the J-1 visa program.
This form indicates that the SEVIS fee has been paid, and will be required for your J-1 visa appointment at the US Embassy or Consulate.
This fee is paid for you and you can obtain your information as to how to print out this receipt on your profile under the visa section. This form must also be part of your important documents that you bring with you to the United States.