You use Nitro Pro to export form data as a separate FDF file (form data format). An exported FDF file is much smaller than the original PDF form file, making it much more convenient for distributing to others. You can email an FDF file to another user who can then import the data into a PDF file, or you can use FDF files to save form data locally, as well as to import data into your forms.
When you import data into a PDF form, the form must contain fields having the exact same names as the fields from which the data was exported. Field names are case-sensitive. Nitro Pro ignores all imported field data where the field names do not match the names from the exported file.