The server has fulfilled the request but there is no new information to send back. If the client is a user agent, it SHOULD NOT change its document view from that which caused the request to be sent. This response is primarily intended to allow input for actions to take place without causing a change to the user agent's active document view. The response MAY include new metainformation in the form of entity-headers, which SHOULD apply to the document currently in the user agent's active view.
The 204 response MUST NOT include a message-body, and thus is always terminated by the first empty line after the header fields.