It used to be that only application developers knew what APIs were, but things have changed to the point where there are entire conferences dedicated to APIs, websites track them, and people can make a living from doing API reviews. CEOs tout their own APIs in keynote speeches, and CMOs allocate budget to API development. The fact is, however, that what an API is and does hasn’t changed. Functionally, APIs were created to expose data to, and across, applications. Originally based on SOAP/XML endpoints, they evolved into Web-based services that enabled ecommerce, data and communication transactions. Before long, it became clear that there isn’t much one can do online unless it involved an API.