Status code

Also written: HTTP status codes, 200, 201, 400, 401, 403, 404, 409, 429, 500, 503

The number that starts an HTTP response and says how the request went: 2xx means success, 4xx the client's mistake, 5xx the server's problem. Common codes are 200 OK, 201 Created, 301 moved for good, 302 moved for now, 400 Bad Request, 401 not identified, 403 known but not allowed, 404 Not Found, 409 Conflict, 429 Too Many Requests, 500 Server Error and 503 Service Unavailable.