What is Application Programming Interface (API)?
An Application Programming Interface (API) is exactly what it sounds like. It is a type of interface where an application is programmed. Specifically speaking, an API is a set of subroutine definitions, protocols, and tools, all of which are used for building application software. An API may be for a web-based system, operating system, database system, computer hardware or software library.
The primary purpose of an API is to help developed use certain technologies to build applications. These APIs contain various components that make it easier for the developer to create programs.