What is a Linux Shell?

It occurred to me recently that there are many shells available, but I’m always interacting with a specific one. In the beginning was the Bourne shell which was highly functional, but all of us are now using the Bourne-Again SHell, or BASH as it might be acronymed. Technically it’s the GNU project’s official shell, but to the rest of us it’s the black screen with the white letters that we type into.

If you’re using a window manager like KDE or Gnome you will be familiar with ‘terminals’. Terminals are the windows that contain shells in a window manager - they are not themselves shells. You can also find a shell if you use telnet or ssh to login to your account on a computer.

Basically a shell is a program that takes your keyboard input and figures out what you’re trying to make the computer do. If you type the name of a program it’ll run a program. If you tell it to show you all the files in a given directory it’ll show you some files. There are some fancy things that can be done with shells now, such as writing code to be executed on the fly or, to a lesser degree, tab autocomplete of filenames.

I recommend you get familiar with the workings of your shell (probably BASH). If you end up spending any time working in it (and if you use Linux - you will) then you’ll enjoy knowing the shortcuts that reduce your repetitive workload.