The MIME type application/vnd.xfdl is used to denote the XFDL file type and the encoding associated with it. The category for this MIME type is "application".

XFDL is a format that is used to securely transmit XML documents over the web. XFDL stands for Extensible Forms Description Language and is a secure format used for the secure transmission and reception of legally binding, complex business documents over the Internet. This format is mainly used by e-commerce entities and is designed to represent the complex business web forms on the web. It is entrusted to provide full non-repudiation of contractual forms, thereby making them legally binding.

This is enabled by the format"s capability to support multiple overlapping digital signatures and fully auditable transaction records. An XFDL document is protected through common http encryption standards while it is being transmitted. Built-in encryption for the format has been proposed but it has not been implemented yet. This encryption will enable the document to be encrypted while it is residing within a storage system.

XFDL is a cross-platform language and hence can be used on all the common platforms. The file containing an XFDL document can take on the following extensions � XFDL, XFD, and FRM.