19.0 Working with the Shell

Although graphical user interfaces have become very important and user-friendly, using them is not the only way to communicate with your system. A command line interpreter, in Unix/Linux called a shell, provides a highly flexible and efficient means for text-oriented communication with your system.

In administration, shell-based applications are especially important for controlling computers over slow network links or if you want to perform tasks as administrator on the command line.

This chapter deals with a couple of basics you need to know for making efficient use of the command line: the directory structure of Linux, the user and permission concept of Linux, an overview of important shell commands, and a short introduction to the vi editor, which is a default editor always available in Unix and Linux systems.