And Why Should I Care?
In its simplest terms, and API allows one program to include the functionality from another program without importing the code from the second program.
Let’s Consult an Expert
Q: Hey Siri! What is an API?
A: “I found the following information that may be helpful:”
Wikipedia
Application programming interface
In computer programming, an application programming interface (API) is a set of routines, protocols, and tools for building software applications. An API expresses a software component in terms of its operations, inputs, outputs, and underlying types.
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https://en.wikipedia.org/wiki/Application_programming_interface
Siri is an excellent example of APIs in action. Siri knows how to query Wikipedia using the Wikipedia API, display a restaurant menu using the Open Table API, or get directions using the Apple Maps API. Without APIs, the Siri application would need to have to code all of that functionality in the application. To code all of that functionality, the Siri application would be huge! Siri, therefore, is not feasible without APIs.
APIs exist in all kinds of forms. Windows APIs are used by desktop applications to access the file system, turn on the web cam, etc. Google Maps APIs can be combined with Niantic APIs to create an application to show you where your favorite Pokémon are spawning. Amazon Echo is based on the Alexa Skills Kit, which Amazon defines as, “… a collection of self-service APIs, tools, documentation and code samples that make it fast and easy for you to add skills to Alexa.”
Why Should I Care About APIs
Because they are in constant use around you, and affect your privacy while providing opportunities.
The Internet of Things (IoT)
APIs power the connection of machines and services, making it possible for your modern refrigerator to detect a water filter that needs replacing, and automatically order a new one from Amazon. Scary convenience that will need manage. Why should your fridge need your credit card number anyway? Maybe it is the fridge that is ordering all those late-night pizzas.