In order to encourage corporate users of electronic documents to extend XPS for their needs and, thus, to increase the number of XPS users. We can assume that the standardization of XPS and adding of the word “Open” to the name were made by Microsoft That is not a standard from the new specification that is a standard. OXPS or OpenXPS or Open XML Paper Specification is an XPS that was raised in 2009 to international standard (ECMA-388) and was renamed to separate the previous specification The article here is going to provide you with information about the differences between XPS and OXPS formats and describe OXPS files. All internal parts of the archive are either text files written in XML-based language or binary resources, such as OpenType fonts or images. XPS file is internally represented by a ZIP archive containing one or more documents, in the traditional meaning of this word, and all the necessary resources for You’ve learned that XPS is one of the static PDLs with a fixed layout.

From the article about XPS you have got familiar with XPS files.

Opening oxps file converter