What is a CLI (command line interface)?

The first time I looked up "command line interface," I learned it was something you use inside a terminal—that window where developers type inscrutable commands in a pixelated-looking font. Right then and there, I dismissed the command line as something that only capital-d developers could use. Then vibe coding tools started blurring the line between who's technical and who isn't, and I started to flirt with the idea of learning CLI again. What I discovered is that it's not as intimidatin