Open XML Paper Specification (also referred to as OpenXPS) is an open specification for a page description language and a fixed-document format. Microsoft developed it as the XML Paper Specification (XPS). It is an XML-based (more precisely XAML-based) specification, based on a new print path (print processing data representation and data flow) and a color-managed vector-based document format that supports device independence and resolution independence.
A POT file is a template created by PowerPoint, a program used to create slide show presentations. It contains the default layout, formatting, and styles for a slide show. POT files are used to create multiple .PPT files with the same formatting.