RFC 2068

9.7 DELETE

   The DELETE method requests that the origin server delete the resource
   identified by the Request-URI. This method MAY be overridden by human
   intervention (or other means) on the origin server. The client cannot
   be guaranteed that the operation has been carried out, even if the
   status code returned from the origin server indicates that the action
   has been completed successfully. However, the server SHOULD not
   indicate success unless, at the time the response is given, it
   intends to delete the resource or move it to an inaccessible
   location.

   A successful response SHOULD be 200 (OK) if the response includes an
   entity describing the status, 202 (Accepted) if the action has not
   yet been enacted, or 204 (No Content) if the response is OK but does
   not include an entity.

   If the request passes through a cache and the Request-URI identifies
   one or more currently cached entities, those entries should be
   treated as stale. Responses to this method are not cachable.