Customized 404 messages, especially on Apache

Customized 404 messages, especially on Apache

A Web author may wish to "customize" error messages that are sent to the browser (or other client) when a requested resource is not found. Normally the server in such cases just sends a general HTTP error code 404 (conventionally called and displayed as "Not Found"), and the browser then takes a general action that it applies in all such cases. So there is nothing site-specific. And there might be a reason why an author wishes to make something site-specific to happen.