IN THIS CHAPTER
Understanding the Linux shell
Using the shell from consoles or terminals
Using command history and tab completion
Connecting and expanding commands
Understanding variables and aliases
Making shell settings permanent
Using man pages and other documentation
Before icons and windows took over computer screens, you typed commands to interact with most computers. On UNIX systems, from which Linux was derived, the program used to interpret and manage commands was referred to as the shell.
No matter which Linux distribution you are using, you can always count on the fact that the shell is available to you. It provides a way to create executable script files, run programs, work with filesystems, compile computer code, and manage the computer. Although the shell is less intuitive than common graphic user interfaces (GUIs), most Linux experts consider the shell to be much more powerful than GUIs. Shells have been around a long time, and many advanced features that aren't available from the desktop can be accessed by running shell commands.
The Linux shell illustrated in this chapter is called the bash shell, which stands for Bourne Again Shell. The name is derived from the fact that bash is compatible with the one of the earliest UNIX shells: the Bourne shell (named after its creator Stephen Bourne, and represented by the sh command).