After this tutorial you are able to code a cool bot with many commands and a level system.
Did you ever want to write your own bot but you think you are too bad for it or you don't have motivation to do so? Stop thinking that way. Writing discord bots using discord.js is really, really, easy if you know some javascript basics.
In this tutorial we will use some ES6, which makes javascript more powerful. If you have never heard of ES6, I'll explain some stuff whenever I use it. Found a mistake? Just comment.