Recs.
Updated
AsciiDoc is a markup language that allows the creation of text documents for writing notes, documentation, articles, books, E-books, slideshows, web pages and blogs. AsciiDoc files can be translated to many formats including HTML, PDF, EPUB, man page using an assortment of open-source tools as the format specification was designed to produce the ubiquitous DocBookXML as its primary output..
Specs
Pros
Pro Native support for colored output
AsciiDoc has offered the ability to define both the color of any text output as well as its background, almost since its inception. It accepts several standard chromatic notations for them, too, including hexadecimal and decimal RGB values, decimal HSL and named CSS.
Pro Embedded metadata
The AsciiDoc standard defines a number of metadata values which can be defined inside a document primarily for contextual purposes that aren't rendered in its standard output such as author, date, license, document title and version, etc. These can be especially useful when searching through a large number of files/documents or documenting the evolution of one as part of a larger codebase.