As an alternate to filling in a PDF form manually, you can import file data from a text (TXT), Extensible Markup Language (XML), Acrobat Form Data Format (FDF), XML Data Package File (XDP), FormFlow99 Data Files (XFD), or Acrobat XFDF (XFDF) file into a PDF form. Some file formats are available only when you import the data into particular PDF forms, such as a PDF form created in Adobe LiveCycle Designer.