An API, or Application Programming Interface, is a defined set of rules and methods that allows one software system to communicate with another. It specifies how applications can request data, submit information, trigger functions, or access services without needing to know how the other system is internally implemented. APIs commonly use structured formats such as JSON and communication protocols such as HTTP.
APIs are fundamental to modern software integration. A weather application can use an API to retrieve forecast data, while an industrial platform might use APIs to collect sensor readings, send commands to equipment, or connect analytics with operational systems. REST, GraphQL, and SOAP are common API approaches used for different integration requirements.
