status code

status code — A short number in an HTTP response that says what happened. 200 means OK, 404 means not found, 500 usually means the server broke.

Status codes are the web's quick signals. When a request fails, the status code is usually the first clue — it tells you whether the server couldn't find what you asked for, refused to give it to you, or fell over trying.

"What status code did you get?" "It's returning a 500."

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HTTPresponserequest404