02: Course Motivation and Overview

The purpose of this course is to teach you JavaScript by teaching you how to make professional websites that accept money from customers. This seems like a simple task, but weirdly not many programmers actually learn how to do this. I never learned how to do it in school or at any job I worked. I had to teach myself how to do something as "simple" as accepting credit cards online. For some bizarre reason, nobody really teaches how to accept money from people online, despite the importance of payments online.

The answer you get is usually, "Just use Stripe." Even with advanced payment processors like Stripe, Adyen, Alipay, and Paypal you still have a lot of complexity in your application. What kind of payments do you need? Subscription? One-time credit card? Is this a marketplace? How do you handle refunds? How do you confirm payment? No, seriously. Have you actually tried to confirm a payment? What happens if you miss a callback? What about credit card fraud? Did you know most of these payment companies do almost nothing to stop fraud? Did you know if you get hit with a charge back that you will have to pay $15-$30 to resolve it, and you might lose the original payment too?

Everyone thinks "just use Stripe" is simple, but there's many scenarios that sabotage that simplicity. Take "pay what you want" models as an example. Let's say you want to offer up your music to people and let them choose how much to pay. They can give you zero dollars, one dollar, or one-hundred dollars. Seems easy enough right? Oh, silly person, you haven't ran into carding.

Carding is where a hacker will buy a ton of stolen credit card numbers, usually gathered from a previous data hack. This person is called a "carder" and "carding" is where they take all of the cards and try to determine if any are still viable, and remove any credit cards that have been canceled. To do this they need to conduct a large scale series of test payments in some anonymous way. They hand out the batch of cards to a bunch of accomplices, and then those accomplices hit any online retailer that offers something for $1...like your music website with it's $1 "pay what you like" model.