What is an API?
An Application Programming Interface (API) lets software components communicate with one another. Web developers can use an API to integrate third-party software with their own. For example, a software company might offer an API version of a Web-based product so developers could integrate it with their own software rather than using the product's user interface.
Each API has its own set of standards and programming instructions. Users typically refer to documentation to know how to submit requests to a Web server and interpret its responses.