Web APIs are everywhere. Just browse any technology news website and you are likely to read something about the latest product launching an open API. Companies are making huge investments in providing APIs to internal developers, partner organizations, and public developers. APIs that were once used to solve integration problems have now become the backbone for an organization’s digital strategy.
What Are APIs?
An API, or application programming interface, is the specification of how one piece of software can interact with another. It is best thought of as a contract between software and the developers using it.
As an example, if you provide a display message to the confirm dialog API inside a browser, then the browser will display the message inside of a pop-up dialog and offer OK/Cancel buttons to proceed when the user presses OK, or cancel if the user presses Cancel:
if(window.confirm("Do you really want to leave?")){window.open("done.html","Thanks for visiting!");}
Using the preceding window.confirm() API results in a browser confirmation dialog:
Traditionally, APIs have always been part of software development. Operating systems such as Microsoft Windows and Mac OS or mobile platforms such as iOS and Android offer APIs that allow developers to build software on top of their platform. Developers depend upon these APIs to exist, operate ...
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