The XML Paper Specification (XPS) makes modern documents possible for all. Simply put, XPS describes electronic paper in a way that can be read by hardware, read by software, and read by humans. With XPS, documents print better, can be shared easier, be archived with confidence, and are more secure.
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The XPS Document Writer allows you print data to a XPS file (creates it)
When Microsoft was forced by Adobe to *not* include writing into .pdf
files in MS-Office, so Microsoft's solution was to provide yet another
document format. You only need the XPS viewer and/or printer if you
actually do get XPS documents.
Adobe claimed their doc format was an open standard. When Microsoft
attempted to implement that doc format, now Adobe proved themself a
liar. However, although XPS may get certified as a doc standard, it
won't be an open standard if Microsoft is the only one having control
over it.