This document specifies two distinct file formats associated with InfoPath electronic forms:
InfoPath Form File Format: This is the format for InfoPath form files, which are used to store data for a form that has been filled out. The format is introduced in section 1.3.1 and described in section 2.1.
A form file is used to store the data of an electronic form that has been filled out by a user. It is an Extensible Markup Language file, as described in [XML] that conforms to the XML Schema of the associated form template. The associated form template specifies how a form server will render and edit the data in the form file using a Web browser. The format for the associated form template is described in [MS-IPFF2].
For example, an expense report submitted by an employee can be represented as a form file. It will contain all the data in the report, such as the total amount spent, date and employee. The form file will have an associated form template that specifies how that form file can be rendered and edited in a Web browser.
InfoPath Property Promotion Format: This format is used to communicate to a SharePoint document library which fields inside an electronic form will be displayed as columns in the document library. The format is introduced in section 1.3.2 and described in section 2.2.
A property promotion file is used to communicate to a SharePoint document library which fields inside an electronic form will be displayed as columns in the SharePoint document library. For example, in a document library used to collect expense reports, each of which is a form file submitted by an employee, this format can be used to make the library display the total amount and the submitter of the report as columns.