This is the base module for the implementation of the `Factur-X <http://fnfe-mpe.org/factur-x/factur-x_en/>`_ and `ZUGFeRD <https://www.ferd-net.de/standards/was-ist-zugferd/index.html>`_ standards. The standard Factur-X 1.0 is the same as ZUGFeRD 2.1 (the name Factur-X is always used in France, whereas in Germany many people use the name ZUGFeRD). It is a standard based on `CII <http://tfig.unece.org/contents/cross-industry-invoice-cii.htm>`_ (Cross-Industry Invoice) for electronic invoicing.

The great idea of the Factur-X/ZUGFeRD standard is to embed an XML file inside the PDF invoice to carry structured information about the invoice.