When I try and open an excel workbook file this message pops up...

The information you opened contains automatic links to information in
another workbook. Do you want to update this workbook with changes made to
the other workbook?

-To update all linked information, click Yes.
-To keep the existing information, click No.


If anyone knows anything about what this message means please let me know.
The workbook I am working in is a copy of another workbook. I did make
changes to the copy, it is not the same as the original.