APIs — Application Programming Interfaces — are waiters. What does that mean exactly? Well, MuleSoft explains it like a restaurant. You sit down at your table, persuing the various delicacies available for your choosing. You know the kitchen will be able to make your order, but how do you let the kitchen know what you want? And how does the kitchen get you your food? Surely, you can’t do it yourself so this is waiters (or APIs) come in. An API is a messenger that takes requests and tells a system what you want to do. Then, the API will return the response back to you.

Real API examples are third-party travel sites. When you use services such as Kayak or Priceline, they are interacting with airlines’ and hotels’ APIs. You tell them what you want, they tell the companies, and then they give you the companies’ responses.

In essence, APIs rule the internet. The web (did I use those right??) would be far less connected that what we see today. They connect the web, allowing developers, applications, and sites to tap into databases and services (or, assets)—much like open-source software. APIs do this by acting like a universal converter plug offering a standard set of instructions.

Get it? Got it? Good! Now you have a basic (emphasis on basic) understanding of how APIs work. You can try out our example below to get a better understanding of the mechanics behind APIs or watch our video about getting started with APIs.

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Side note: often on like third-party travel sites, there aren’t Southwest flights. I usually use Google Flights, so I can’t speak for everyone, but does that mean Southwest doesn’t allow third-party access to their APIs? And what would be the motive for doing so?