What is the Command Line? CLIs from First Principles

Eventually it happens to every new WordPress developer: someone blithely tells you to just “pop over to the command line” and suddenly you feel like a fraud. You shouldn’t–everyone is new once, and someone who won’t explain what they mean by that to you is a jerk–but you do. Most new developers hit that point, often at a local meetup or WordCamp. This is a tutorial for anyone who’s currently stuck there. And for people who are no longer stuck there, I’ll try to include enough details and anecdotes that you’ll learn a little something too.