ReStructuredText

reStructuredText (RST, ReST, or reST) is a plain-text markup language primarily used for technical documentation and other textual data. It serves a similar role as Markdown but includes additional semantic features for more complex document structuring. Prominent, large-scale, open-source projects that rely on reStructuredText include the Python programming language community for its official documentation, the Linux kernel docs, CMake, and the LLVM compiler project.

It is part of the Docutils project of the Python Doc-SIG (Documentation Special Interest Group), aimed at creating a set of tools for Python similar to Javadoc for Java or Plain Old Documentation (POD) for Perl. Docutils can extract comments and information from Python programs, and format them into various forms of program documentation.

In this sense, reStructuredText is a lightweight markup language designed to be both processable by documentation-processing software such as Docutils, and be easily readable by human programmers who are reading and writing Python source code.