In principle, anyone can download the GNU and Linux sources from the Internet and assemble their own operating system including tools. However, the effort is not to be underestimated and hardly feasible without expert knowledge. Fortunately, there are communities and companies that offer Linux distributions. Distributions are completely prepared packages with utilities and usually many application packages that allow easy installation of a Linux system. The best known distributions are Ubuntu, Suse and Redhat. In addition, however, there are countless derivatives that are suitable for a wide variety of applications. Most of them can also be obtained and used free of charge from the Internet.