```js
const express = require('express');
const app = express();
/*
app comes with a use method, which is how you invoke most middleware in express
app works differently depending on the situation
in the situation below, use takes one arg, the middleware you want to run
*/
// with the method below, you can go to localhost:3000 and statically see any file (image, css, js, etc.) in the public folder
app.use(express.static('public'));
app.listen(3000, () => 'listening on port 3000');
```