Learning

1. The Art of Command Line is a very good resource to discover what to learn.

2. To discover what a command does, generally type:

   man <command>
   <command> -h  # or
   <command> --help
   

3. If you install tealdeer, you can type:

   tldr <command>
   

   This will show you example command usage with easy to understand descriptions.

4. explainshell.com maps a command and its args to the man page explanations.

Tips

1. Spam the Tab key.
2. Learn to navigate lines / words – Ctrl A / Ctrl E; Alt B / Alt F.
3. Learn to delete by line / word – Ctrl U / Ctrl K; Ctrl W / Alt D.
4. Learn to undo edits – Ctrl Shift Underscore.
5. Interrupt / cancel the current input or command – Ctrl C.

You are dangerous when you know a command exists, and run it without knowing what it does.