API

An API acts as a bridge between software components, enabling one application to access the features or data of another securely and efficiently. APIs support communication through defined endpoints, often using HTTP, making them vital for web applications, cloud services, and mobile apps.

They come in types like REST, SOAP, and GraphQL, and can be public, private, or partner-specific. APIs are foundational in microservices architecture, supporting modular development and real-time data exchange.

Popular use cases include payment gateways, social logins, and third-party integrations. With proper authentication and rate-limiting, APIs ensure secure interactions across platforms. They also simplify development by allowing reuse of existing services instead of building new ones from scratch.