HTTP status codes are issued by a server in response to a client's request made to the server.
Below are some typical status codes.
| Code | Meaning |
| --- | --- |
| 200 OK | Standard response for successful HTTP requests. The actual response will depend on the request method used. In a GET request, the response will contain an entity corresponding to the requested resource. In a POST request, the response will contain an entity describing or containing the result of the action. |
| 400 Bad Request | The server cannot or will not process the request due to an apparent client error. |
| 401 Unauthorized | Similar to 403 Forbidden, but specifically for use when authentication is required and has failed or has not yet been provided. |
| 403 Forbidden | The request contained valid data and was understood by the server, but the server is refusing action. |
| 404 Not Found | The requested resource could not be found but may be available in the future. Subsequent requests by the client are permissible. |
| 409 Conflict | Indicates that the request could not be processed because of conflict in the current state of the resource, such as an edit conflict between multiple simultaneous updates. |
| 500 Internal Server Error | A generic error message, given when an unexpected condition was encountered and no more specific message is suitable. |