View webinar: http://www.eurostarconferences.com/community/member/webinar-archive/webinar-81-api-testing-the-heart-of-functional-testing An API, or Application Programming Interface, is a collection of functions that provide much of the functional capabilities in complex software systems. Most customers are accustomed to interacting with a graphical user interface on the computer. But, many customers do not realize the much of the functionality of a program comes from APIs in the operating system or program's dynamic-link libraries (DLL). So, if the business logic or core functionality is exposed via an API call then and if we want to find functional bugs sooner than API testing may be an approach that provides additional value in your overall test strategy. Additionally, API testing can start even before the user interface is complete so functional capabilities can be tested while designers are hashing out the "look and feel." API testing will not replace testing through the user interface, but it can augment your test strategy and provide a solid foundation of automated tests that increase your confidence in the functional quality of your product.