An API, or Application Programming Interface, is a software intermediary that allows two or more computer programs to communicate with each other. APIs are a way to extract and share data within and across organizations, and they can be custom-built for a particular pair of systems or a shared standard allowing interoperability among many systems. APIs can be thought of as a contract of service between two applications, defining how the two communicate with each other using requests and responses.
APIs have been around almost as long as computing, but modern web APIs began taking shape in the early 2000s. Modern APIs adhere to specific standards, typically HTTP and REST, which enable them to be developer-friendly, self-described, easily accessible, and understood broadly. APIs are used to integrate new applications with existing software systems, which increases development speed because each functionality doesn’t have to be written from scratch.
In summary, an API is a way for two or more computer programs to communicate with each other, allowing them to share data and functionality. They are a contract of service between two applications, defining how the two communicate with each other using requests and responses. APIs have been around for a long time, but modern web APIs began taking shape in the early 2000s and adhere to specific standards, typically HTTP and REST.
