Current documentation is built on top of Sphinx documentation generator. It is released under the terms of the Creative Commons BY-NC-ND 4.0 International License.

We're folllowing GitFlow:

• master branch for the curent major stable release,
• develop branch for next major release.

GLPI installation documentation is currently visible on ReadTheDocs.

You'll just have to install Python Sphinx, it is generally available in distributions repositories for Linux.

If your distribution does not provide it, you could use a virtualenv:

$ virtualenv /path/to/virtualenv/files
$ /path/to/virtualenv/bin/activate
$ pip install sphinx

Once all has been successfully installed, just run the following to build the documentation:

$ make html

Results will be avaiable in the build/html directory :)

Note that it actually uses the default theme, which differs locally and on readthedocs system.