G.0 Working with the Shell

Graphical user interfaces are increasingly becoming important for Linux, but using the mouse is not always the best way to perform daily tasks. The command line provides high flexibility and efficiency. The first part of this appendix provides an introduction to the Bash shell. It is followed by an explanation of the user permissions concept in Linux and a list of the most important commands. It then closes with a description of the vi text editor.

WARNING:Some commands used at the terminal prompt can delete data and cause your operating to cease functioning. Only administrators and advanced users should execute shell commands.

Text-based applications are especially important for controlling older Linux computers that do not have the resources for demanding display systems. Virtual consoles are used in this case. Six of them are available in text mode (Alt+F1 through Alt+F6). The seventh console is reserved for X.