The paper forms barcode object is a two-dimensional (2D) barcode that is encoded with an industry standard PDF417, QR Code (Version 2), or DataMatrix (the ECC200 model) symbology. It includes an intelligent calculation script that encodes the data captured in a form’s fields.
You select the form fields to be encoded by the paper forms barcode. However, because the barcodes have limited storage capacity, it is important that you select only required fields.
After you add a paper forms barcode to the form design, you specify its properties so that it behaves in the manner appropriate for your requirements. Using the Object palette, you can define these properties and others for the paper forms barcode:
The Paper Forms Barcode object encodes data that users type in a fillable PDF form. The use of paper forms barcodes for paper forms processing requires Adobe LiveCycle Barcoded Forms ES (separate license required).
Users must use Acrobat or Adobe Reader 7.0.5 or later to fill a form using QR Code or Data Matrix Paper Forms Barcode. Therefore, form authors must not save the form as either Acrobat 7.0.5 Compatible or Acrobat 6.0.2 Compatible.
Users must use Acrobat or Adobe Reader 7.0.5 or later to fill a form that includes the PDF417 Paper Forms Barcode. Therefore, form authors must not save the form as Acrobat 6.0.2 Compatible.
See also 

Layout properties in the Layout palette

Border properties in the Border palette
Accessibility properties in the Accessibility palette

How the paper forms barcode works