What is a REST API?

A REST API is an interface that exposes resources over HTTP using a small set of verbs and predictable URL patterns. REST, short for Representational State Transfer, is an architectural style rather than a strict protocol, but the common practice of using GET, POST, PUT, PATCH, and DELETE against resource URLs has become the default way to integrate web services.

Definition

In a typical REST design, each resource has its own URL, and operations on the resource correspond to HTTP verbs. A product might live at /products/123, retrievable with GET, modifiable with PATCH, and removable with DELETE. Responses are usually JSON, status codes signal outcomes, and headers carry metadata such as caching directives and authentication tokens.

Why it matters

REST APIs are the lingua franca of modern commerce stacks. PIM systems, OMS, payment providers, search engines, and content platforms expose REST endpoints that storefronts and integration layers consume. Their simplicity, broad tooling support, and explicit HTTP semantics make them well suited to public integrations.

REST vs. GraphQL

REST excels at clear, resource-oriented interactions and benefits from native HTTP caching. GraphQL excels at flexible reads where the client decides on the shape of the response. In practice, most composable commerce stacks combine both: REST for service-to-service integration and webhooks, GraphQL or BFFs for the frontend. The choice depends on team skill, ecosystem, and how predictable client needs are.

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