GET retrieves a representation and should not intentionally change server state. POST commonly creates a subordinate resource or triggers a server-side operation. PUT replaces the representation of a resource at a known URI and is intended to be idempotent. PATCH applies partial modifications. DELETE removes a resource and is also intended to be idempotent.

HEAD is similar to GET but asks for response headers without the response body. It is useful for checking existence, metadata, content length, or cache information.

Do not select methods simply because they sound convenient. Method semantics affect caching, retries, proxies, client behavior, and API correctness.