API

A set of rules that allows different software entities to communicate with each other.

API (Application Programming Interface) is a set of protocols, routines, and tools for building software applications. APIs specify how software components should interact. For instance, when you use a social media app and it displays your timeline, an API retrieves that data from the server. APIs can be public, like those provided by Google Maps for location services, or private, internal to a company for specific business functions.