The HTTP response status code 301 Moved Permanently is used for permanent redirection, meaning current links or records using the URL that the 301 Moved Permanently response is received for should be updated to the new URL provided in the Location field of the response. This status code should be used with the location header.
If the 301 status code is received in response to a request of any type other than GET or HEAD, the client must ask the user before redirecting.