Simple definition
An HTTP response carries a status code, headers, and optionally a representation body returned by a server.
Purpose and use
An HTTP response reports how a server or intermediary handled a request.
How does it work?
The status code describes the HTTP-level result; headers provide information such as content type, caching rules or a redirect destination.
Example and verification
For a blank screen despite status 200, inspect received content and dependent requests rather than only the first response.
Points to watch
A response can originate from a cache, proxy or application error page. HTTP status alone does not prove business-level success.
In short
Interpret status, headers and content together with the context of the original request.