Now that you're configured to allow customers to complete their purchases, let's turn our attention to what happens after the sale: the order process.

Magento 2 has a carefully crafted process for how orders flow from checkout to shipment. Once we understand the "core" flow, we can begin to explore how changes to orders, such as cancellations and refunds, fall into this process.

To understand this process better, let's take a look at two examples of new orders in the Magento 2 backend. Orders are accessed by going to Sales | Orders in the Magento backend.

The first order shown, 000000003, is an order paid for by check or money order. Since the funds have not yet been received, it has a status of Pending. The second order in the list, 000000002, was also paid by check, but the money was received. The order is shown as Complete, because the order has been shipped. Finally, the last order in the list is shown as Processing because the payment has been received, but the order has...