A REST API is an HTTP API organised around resources identified by URLs and manipulated with standard methods such as GET, POST, PUT, PATCH and DELETE.

What is a REST API?

REST API, explained

REST (Representational State Transfer) is an architectural style rather than a standard. In practice, a "REST API" exposes resources like /invoices/inv_123, uses HTTP methods for actions, HTTP status codes for outcomes, and usually JSON for payloads.

REST APIs are commonly described with an OpenAPI document, which tools use to generate documentation, SDKs and tests, and to detect breaking changes between versions.

API: An API (application programming interface) is a defined contract that lets one piece of software request data or actions from another without knowing how it is implemented.
OpenAPI Specification: The OpenAPI Specification is a standard, language-agnostic format (YAML or JSON) for describing HTTP APIs: their paths, operations, parameters, schemas and authentication.
API versioning: API versioning is the practice of exposing multiple versions of an API at once so providers can ship breaking changes while existing clients keep using the version they were built for.

REST API, explained

Related terms

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