Which HTTP response status indicates an internal server error?

The status code 500 signifies an internal server error, which indicates that the server encountered an unexpected condition that prevented it from fulfilling the request. This error is a generic response that indicates a problem on the server side, rather than a client-side issue. The 500 status code falls within the range of 500–599, which is specifically reserved for server error responses, highlighting that something has gone wrong on the server itself.

Understanding this code is crucial for troubleshooting and diagnosing server problems. When a client receives this response, it signifies that the server is operational but is unable to perform the request due to an internal issue that may need to be addressed by the server administrators.

In contrast, the other status codes listed represent different conditions: a 503 response indicates that the server is currently unavailable (possibly due to being overloaded or down for maintenance), a 301 response denotes a permanent redirect to a new URL, and a 404 response signals that the requested resource could not be found. Each of these codes relates to different scenarios in client-server interactions, but only the 500 code represents an internal server error.