Sphinx or mkdocs:<p><a href="http:&#x2F;&#x2F;www.sphinx-doc.org&#x2F;en&#x2F;latest&#x2F;" rel="nofollow">http:&#x2F;&#x2F;www.sphinx-doc.org&#x2F;en&#x2F;latest&#x2F;</a><p><a href="http:&#x2F;&#x2F;www.mkdocs.org&#x2F;" rel="nofollow">http:&#x2F;&#x2F;www.mkdocs.org&#x2F;</a><p>Which make it easy to create html, pdf, epub, latex formats, etc.<p>I like to create a user guide, developer guide, and ops guide for each large project.