The dotenv module makes configuration of environment variables that you don't want to, say, commit to GitHub, easy. You load it into your Node.js application:

const dotenv = require('dotenv').config()

This loads a .env file in the same directory that the Node.js file is in, which is in the following format:

KEY=value

And it is then accessible in your application via the process.env global variable:

let key = process.env.KEY // 'value'

Now that we know more about the libraries and services we're using, let's get a test connection program set up!