Understanding the Linux shell

When it comes to the Linux shell, it’s important to understand what exactly the term pertains to. We’ve been using the command line repeatedly throughout the book, but we haven’t yet had any formal discussion about the actual interface through which our commands are entered.

Essentially, we’ve been entering our commands into a command interpreter known as the Bourne Again Shell, or simply Bash. Bash is just one of many different shells that you can use to enter commands.

There are other options, including Zsh, Fish, and ksh, but Bash is the default command shell for the majority of Linux distributions. It’s even available on macOS (although the default on that platform is Zsh nowadays), as well as on Windows by installing the Windows Subsystem for Linux. Therefore, by understanding the basics of Bash, your knowledge will be compatible with other distributions and platforms. While it’s fun to learn other...