IT Concept: API (Application Programming Interface)

APIs define how software components interact. Web APIs (typically REST or GraphQL) allow applications to request and send data over HTTP. For example, a weather app uses a weather API to get forecast data.

REST APIs use standard HTTP methods (GET, POST, PUT, DELETE) and return JSON/XML. GraphQL APIs let clients specify exactly what data they need. API design principles include versioning, authentication, rate limiting, and clear documentation.