For system, network and cloud administrators

What is a “shell”?

The Bourne Shell: /bin/sh

The shell is one of the most important parts of a Unix system and that’s why developers and admins around the world rely so much on it. It’s basically a program inside which the user can run commands and create shell scripts. Unix programmers used the shell as a programming environment too. In fact, a lot of the important parts of the Unix system itself are … shell scripts.


What is “cat”?

cat is a Unix command that will simply output the contents of a file or multiple files.