======
Ubuntu
======

`Ubuntu <ubuntu>` is an open-source operating system distribution
built on `Linux <linux>` and `GNU <gnu>` software.

External Documentation
======================

- `Ubuntu Web Site <ubuntu-site_>`_

Supported Versions
==================

The following versions of Ubuntu are regularly tested with our code
crafting tools:

- 18.04
- 20.04

.. _ubuntu-site: https://ubuntu.com