Imagine a scenario where you enter a coffee shop. You go to your barista and ask for a frappuccino. The barista enters your order on their computer or passes your order along to the other barista. After making your payment, you then wait for your order to come. If it comes, you can start enjoying your coffee. And if there was a miscommunication between you and the barista, you might get a drink you didn't intend to order.
This is a companion discussion topic for the original entry at http://iq.opengenus.org/intro-to-fetch-api/