Application programming interfaces (API) have been around since the 1960s. An API is a set of routines, protocols, and tools for building software applications. Basically, an API specifies how software components should interact. APIs are used when programming graphical user interface (GUI) components. A good API makes it easier to develop a program by providing all the building blocks. A programmer then puts the blocks together. So if they aren’t a new concept, why are they such a hot topic lately?
In short, without APIs, the digital experiences that we expect every day as consumers wouldn’t be possible. Businesses now know that investing in an API strategy can pay significant dividends because they are doing everything from driving information rich marketing campaigns and connecting mobile apps to streamlining internal operations.
APIs do a lot both in mobile and on the web. They’re responsible for nearly everything we do and with just a few taps or clicks, you can order online, book a hotel, rate a song, or download a software. APIs work quietly in the background, making the interactivity we expect and rely upon possible.
There are many different types of APIs for operating systems, applications or websites. Most operating environments, such as MS-Windows, provide APIs, allowing programmers to write applications consistent with the operating environment. Today, APIs are also specified by websites. For example, Amazon or eBay APIs allow developers to use the existing retail infrastructure to create specialized web stores. Third-party software developers also use Web APIs to create software solutions for end-users.
In a nutshell, an API is an interface that software uses to access whatever currency it needs: data, server software, or other applications.