What is the difference between the PUT, POST, and PATCH methods?

PUT is used to create or completely replace a resource at the specified URL. If the resource exists, it will be fully overwritten with the provided data. If it does not exist, a new resource will be created. It is an idempotent method.

POST is used to send data to the server for processing. This can be creating a new resource, submitting form data, or performing some operation. The URL usually points to a "collection" to which the action applies. It is not idempotent.

PATCH is used for partial modification of a resource. Instead of sending a complete representation of the resource, only the data that needs to be changed is sent.

Method	Purpose	Idempotent
PUT	Create / Replace	Yes
POST	Create / Process	No
PATCH	Partial update	No (usually)