XPS Document Format

Ever since the first PC printers appeared, designing a proper file format that could be used for exchanging, viewing, editing and of course actual printing files has been an ongoing challenge.

Adobe started it with PostScript and, later, PDF.

Older Windows versions used the EMF -- Enhanced MetaFile format. However, the continuous advances in printing technology challenged Microsoft to design a new format: XPS -- the XML Paper Specification format.

Introducing the XPS Document Format

XPS can be used to completely describe a document, both in terms how it is to be printed, and in terms of what has to be printed (i.e. the actual content). An XPS file is a ZIP archive of an XML (or, to be more precise for the tech-minded, XAML) file. XML is a special language itself, which has been preferred because it is well-established and easy to use by computer programs.

By using XML, XPS can describe the document in a resolution-independent, vector-based manner. In other words, this means that every part of the document (even individual letters and small images) are stored so that they will not lose any quality when the image is enlarged or shrunk. As a consequence, your XPS documents will look just as well on a business card-sized paper and on an A3 poster.

Furthermore, XPS has a number of special facilities which make it especially appealing to those who work with graphics-intensive documents. Besides support for gradients or transparency, XPS also supports the Windows Color System management technology. As a consequence, there will be no loss of color quality and no color change when viewing XPS documents on different systems -- a problem EMF was particularly vulnerable to.

MadCap Software are just one of many companies that now provide integrated support for XPS documents. 

Windows Vista makes use of XPS in two ways. First of all, XPS is intended as a document viewing format, using the free Microsoft XPS Viewer that ships with Vista. The XPS Viewer allows you to view any XPS file, but this is not where the real strength of XPS comes from. XPS can also be used as a print format, meaning that printers can use XPS to describe documents internally.

The prerequisite for this is that XPS must be able to describe anything that can ever be printed. As a consequence, XPS can be used for anything. It is not a format specialized for text documents, like Word's .doc format -- but can effectively be used for books, posters, flyers, diagrams, circuit schematics, house plans or raster images like screenshots or paintings.

Therefore, XPS is a very effective file exchange format.

Since XPS can render any type of data, and is tightly integrated with Vista, users can exchange XPS files, with the guarantee that they will look the same on any system. Since XPS is standard, a file printed in XPS format on a Windows computer will look the same on another system, even if the program that generated it is not installed. Every program can generate an XPS file by printing to a special, simulated printer. This appears like a regular printer in the printers list, but internally, Windows uses it to generate an XPS file.

XPS is rapidly being adopted by several major companies, including Sharp and HP. Therefore, it is safe to expect that it will soon be a widespread format.

The free XPS viewer is also available, as a download for Windows XP SP2 computers, from the main Microsoft website.