context

About context

From Debian's package description

ConTeXt is a document-production system based, like LaTeX, on the TeX typesetting system. Whereas LaTeX insulates the writer from typographical details, ConTeXt takes a complementary approach by providing structured interfaces for handling typography, including extensive support for colors, backgrounds, hyperlinks, presentations, figure-text integration, and conditional compilation. It gives the user extensive control over formatting while making it easy to create new layouts and styles without learning the TeX macro language. ConTeXt's unified design averts the package clashes that can happen with LaTeX.

ConTeXt also integrates MetaFun, a superset of MetaPost and a powerful system for vector graphics. MetaFun can be used as a stand-alone system to produce figures, but its strength lies in enhancing ConTeXt documents with accurate graphic elements.

ConTeXt allows the users to specify formatting commands in English, Dutch, German, French, or Italian, and to use different typesetting engines (PDFTeX, XeTeX, Aleph, and soon LuaTeX) without changing the user interface. ConTeXt is developed rapidly, often in response to requests from the friendly user community.

From Debian's description of the context package, under that package's license.