The GNU Astronomy Utilities (Gnuastro) is an official GNU package consisting of separate programs for the manipulation and analysis of astronomical data. All the various utilities share the same basic command line user interface for the comfort of both the users and developers. GNU Astronomy Utilities is written to comply fully with the GNU coding standards so it integrates finely with the GNU/Linux operating system. This also enables astronomers to expect a fully familiar experience in the source code, building, installing and command line user interaction that they have seen in all the other GNU software that they use.

For users who are new to the GNU/Linux environment, unless otherwise specified most of the topics in chapters 2 and 3 are common to all GNU software, for example installation, managing command line options or getting help. So if you are new to this environment, we encourage you to go through these chapters carefully. They can be a starting point from which you can continue to learn more from each program’s own manual and fully enjoy this wonderful environment.