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# What is an API?

## The API application programming interface

API is the acronym for _Application Programming Interface_ or application programming interface. This is a set of rules and protocols for creating and integrating software applications. 

These specify how software components must interact, and they allow communication between different systems.

APIs provide access to the functionality or data of an operating system, web system or application. They are used in web development for various purposes. Consideration may be given to allowing integration with other websites, creating custom web applications or mobile applications that communicate with a web service.