può essere utile... *1xx Codes:* (Information) This code class indicates a provisional response, consisting only of the Status-Line with optional headers, and is terminated by an empty line. _Note:_ Since HTTP/1.0 did not define any 1xx status codes, servers MUST NOT send a 1xx response to an HTTP/1.0 client except under experimental conditions. *100* (Continue): An interim response telling the browser the initial part of its request has been received and not rejected by the server. A final response code should be sent when the remainder of the material has been sent. *101* (Switching Protocols): The browser may wish to change protocols it's using. If such a request is sent and approved by the server this response is given. *2xx Codes:* (Success) The two hundred range is reserved for successful responses. Your log file will show these classes of codes for all successful hits. *200* (OK): The request was successful and information was returned. This is, by far, the most co...