Standards to help reduce duplicate transmissions
Idempotency is a method particular to REST APIs with HTTP/HTTPS protocols that makes sure the result does not change even if applied multiple times. If you submit multiple identical requests sequentially, only the first request would get a response that does not change with the subsequent, incoming requests.
HTTP methods and idempotency
| Method | Is the method idempotent? | Does it modify the server's state? | 
|---|---|---|
| HEAD | Yes | No | 
| OPTIONS | Yes | No | 
| GET | Yes | No | 
| POST | No | Yes | 
| PUT | Yes | Yes | 
| PATCH | No | Yes | 
| DELETE | Yes | Yes |