API (Application Programming Interface)
Definition
A set of rules and protocols that allows different software applications to communicate with each other and share data or functionality.
An Application Programming Interface defines how software components should interact. APIs allow developers to use functionality from other services without needing to understand their internal workings. For example, a weather app uses a weather service's API to retrieve forecast data.
APIs come in several styles: REST (the most common web API standard, using HTTP methods like GET, POST, PUT, DELETE), GraphQL (allows clients to request exactly the data they need), SOAP (an older XML-based protocol), and WebSocket (for real-time bidirectional communication).
Modern software development relies heavily on APIs. They enable microservices architecture, third-party integrations, mobile app backends, and platform ecosystems. Understanding API concepts like endpoints, authentication, rate limiting, and documentation is essential for modern web development.
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Related Terms
REST API
techAn architectural style for web services that uses standard HTTP methods to create, read, update, and delete resources, providing a stateless communication interface.
JSON (JavaScript Object Notation)
techA lightweight data interchange format that is easy for humans to read and write and easy for machines to parse and generate.
HTTP (HyperText Transfer Protocol)
techThe foundational protocol for data communication on the web, defining how messages are formatted and transmitted between clients and servers.
JWT (JSON Web Token)
techA compact, URL-safe token format used for securely transmitting information between parties as a JSON object, commonly used for authentication.
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