Doxygen!

Swagger is an open source RESTapi Documentation Tool.

Slate - beautiful static documentation for your API.

Daux.io is a documentation generator that uses a simple folder structure and Markdown files to create custom documentation on the fly. It helps you create great looking documentation in a developer friendly way.

Sandcastle produces accurate, MSDN style, comprehensive documentation by reflecting over the source assemblies and optionally integrating XML Documentation Comments. Sandcastle has the following key features:

Easy Install and Upgrade.npm makes installation and upgrade a, trivial, single command activity. No need to modify your content during upgrades.

ApiGen is the tool for creating professional API documentation from PHP source code, similar to phpDocumentor 2 .

DoxyS is a code documentation tool for C++/C. DoxyS strives to yield a very professional looking output, presenting the the code in a structured easy to navigate set of HTML pages. Easy to use: Just navigate to the root of your code directory and type doxys.

PHP documentation generator based on docblock parsing.

Supported platforms: Visual Studio 2015 incl. Community Edition Visual Studio 2013 Visual Studio 2012 Visual Studio 2010 Visual Studio 2008

NDoc generates class library documentation from .NET assemblies and the XML documentation files generated by the C# compiler (or with an add-on tool for VB.NET).

Natural Docs is an open-source documentation generator for multiple programming languages. You document your code in a natural syntax that reads like plain English. Natural Docs then scans your code and builds high-quality HTML documentation from it.

CppDoc generates HTML documentation for C++ classes, based on your source code and special comments embedded within it. It can produce output that is very similar to the output of Javadoc, and it supports Javadoc tags such as @see, @return , etc. The documentation comments are optional; if you leave them out, CppDoc will still generate a full set of documentation based on class relationships and hierarchy.