Open XPD File
The XPD files typically have two applications of a different nature, namely:
PlayStation Store
In this application, the XPD file is a license file downloaded together with the content from the Sony PlayStation Store.
PlayStation Store is a digital media store available to users of most Sony PlayStation game consoles through the PlayStation Network.
In other words, the XPD is used for Digital Rights Management or DRM and is necessary to transfer games and other downloaded files to the PlayStation Portable or PSP device, according to its acronym.
XPD files are automatically acquired by the PlayStation Network Downloader when files are downloaded from the PlayStation Store for PSP.
XML Pipeline Document
In this case, and well differentiated from the previous one, the XPD file is a web page generated from an XML document, usually through an XSLT transformation.
It is important to note that XSLT is a language for transforming XML documents into other documents of the same XML nature, or even other formats such as HTML for web pages, plain text or XSL format objects.
In this section, the XPD file was developed by Joshua Tauberer to promote GovTrack.us which is a website developed to allow its users to keep track of the bills and, in turn, the members of the Congress of the States United.
Software to work with an XPD file
The files, in neither case, are designed to be opened manually by the user, however, the following software is directly associated with said file, since it is downloaded through said software: