Helpful terminal prompts to clean and repair HD, SDD, and External HD

Learn the shell. zsh is available on older releases, and is the default on newer.

The docs here are going to be in transition for a while, as other systems are using bash.

As for your interest in command-line management, it’s fairly rare that I have to resort to that for troubleshooting or repairs.

More commonly, scripting is a handy tool for automation.

macOS is switching from bash to zsh command shell with Catalina.

If you want to learn the command line, there are various resources.

Here are a few:

https://tidbits.com/2019/12/08/resources-for-adapting-to-zsh-in-catalina/

https://developer.apple.com/library/archive/docum

https://developer.apple.com/library/archive/documentation/OpenSource/Conceptual/ShellScripting/CommandLInePrimer/CommandLine.html

That should keep you busy...

Oh, and sudo is really, really, hazardous. Have backups. And always experiment in a separate non-admin login to isolate the potential for damage, and avoid using sudo until you know what you’re doing.