Since for scientific research often different variants of the Unix operating system are used, the first part of this course will introduce various basic aspects of this operating system. To this end insight in the theoretical principles of operating systems is necessary. Besides this theoretical basis, we shall focus on Linux, especially, shell scripting, commands and processes, regular expressions and working with text files. We will also look at the Python programming language. Since it is very important to correctly interpret numerical results, we shall also focus on reliability and accuracy of computations. Finally, we will give an introduction to the available HPC infrastructure. Using this knowledge, a student must be capable to start tackling computational problems in the field of chemistry.