Application programming interfaces, or APIs, are the de facto mechanism for connecting applications, data, and systems—but they’re also much more.

APIs abstract backend complexity behind a consistent interface, which means they not only allow one kind of software to talk to another, even if neither was designed to do so, but also empower developers to leverage data, functions and other digital assets both more efficiently and in new and novel ways.

Developers have launched new ride-sharing services by combining third-party mapping and navigational APIs with their own first-party data and functionality, for example. Many applications rely on third-party APIs, such as those from Twitter or Google, for authentication. When developers want to add voice commands to an application but lack the time, incentives, resources or expertise to build their own natural language technologies, they can turn to APIs to get the functionality they need.