What Is An API (And What Does This Abbreviation Stand For)?

Discussing technical jargon isn't everyone's favorite pastime, but it's important to understand how the technology we use works, at least on a basic level.

API is one technical term that comes up fairly often, especially in professional settings and discussions about software development. In recent years, this terminology has seeped into mainstream conversations. For example, you might recall the public debate last year when Reddit made some controversial changes to its API, or you might have read something about locating your ChatGPT API key.  

The good news is that the concept is simpler than it seems at a glance, and you don't need to be a programmer or a techie to understand the role APIs play in our lives. 

API is an abbreviation. In API, the "A" stands for application, "P" stands for programming, and "I" stands for interface. Obviously, that alone doesn't really say much, so here's what else you need to know about APIs and how they work.

If you've ever checked the weather using an app, made an online purchase, or watched a Netflix show, you've used an API. So, what is an API? An API is simply a set of protocols that enables computer programs to communicate with one another.

Most apps we use every day wouldn't function without APIs. Take food delivery apps, for example. When you place an order, the app sends an API request that reaches the restaurant you're ordering food from. Similarly, when you're ready to pay for your order, the app sends an API request to a payment processor like PayPal.

What is an API in layman's terms, you ask? Think of it this way. When you're watching television and the volume is too loud, you pick up the remote, point it at the TV set, press the volume down button, and the volume decreases to a more comfortable level. In this analogy, you are sending requests to the TV, while the remote acts like an application programming interface. That is exactly what APIs do — based on the data they receive, they send specific information to another application, which then performs the requested action.

API architecture can be complex, but it is best understood as a framework based on the client-server model. In such a system, the application that sends requests is referred to as the client. The server, meanwhile, accepts requests, processes them, and sends back responses. 

This is exactly how some of the best weather apps work. It's not like they are run by huge teams of meteorologists that manually send you weather information. Instead, weather apps use APIs to automatically retrieve relevant data from various sources, such as meteorological databases, national weather services, forecasting models, and so on.

In other words, the weather app acts as a client and automatically sends requests for information to the server. The server, typically a meteorological organization (or multiple organizations and entities), receives those requests and responds by sending weather data. Obviously, all you see on your screen as a user is up-to-date weather information, both the requests and the responses occur through an API, but now you know the processes that go on behind the scenes.