It's a REPL for Node.js. It has data visualization features, and it also manages npm packages for you, but those are just features. Another way to think of it

It's a REPL for Node.js. It has data visualization features, and it also manages npm packages for you, but those are just features. Another way to think of it is, a different (hopefully better) version of the thing you'd get if you just typed "node" in your terminal.