Old revisions Add to book Export to PDF Fold/unfold all Book Creator Add this page to your book Book Creator Remove this page from your book Manage book (0 page(s)) Help API (Application Programming Interface) An API is a set of protocols, tools, and instruction for implementing software applications. In case of web application development, the API specifies how the system should send requests and what kind of corresponding responses should be expected to receive. The API may include functions like file managements, window/video/character processing to ease the application development process for the 3rd party application developers.