• 300 Multiple Choices
  Indicates multiple options for the resource that the client may follow. It, for instance, could be used to present different format options for video, list files with different extensions, or word sense disambiguation.^[2]
  
  
• 301 Moved Permanently
  This and all future requests should be directed to the given URI.^[2]
  
  
• 302 Found
  This is an example of industry practice contradicting the standard.^[2] The HTTP/1.0 specification (RFC 1945) required the client to perform a temporary redirect (the original describing phrase was "Moved Temporarily"),^[6] but popular browsers implemented 302 with the functionality of a 303 See Other. Therefore, HTTP/1.1 added status codes 303 and 307 to distinguish between the two behaviours.^[7] However, some Web applications and frameworks use the 302 status code as if it were the 303.^[8]
  
  
• 303 See Other (since HTTP/1.1)
  The response to the request can be found under another URI using a GET method. When received in response to a POST (or PUT/DELETE), it should be assumed that the server has received the data and the redirect should be issued with a separate GET message.^[2]
  
  
• 304 Not Modified
  Indicates that the resource has not been modified since the version specified by the request headers If-Modified-Since or If-Match.^[2] This means that there is no need to retransmit the resource, since the client still has a previously-downloaded copy.
  
• 305 Use Proxy (since HTTP/1.1)
  The requested resource is only available through a proxy, whose address is provided in the response.^[2] Many HTTP clients (such as Mozilla^[9] and Internet Explorer) do not correctly handle responses with this status code, primarily for security reasons.[citation needed]
  
  
• 306 Switch Proxy
  No longer used.^[2] Originally meant "Subsequent requests should use the specified proxy."^[10]
  
  
• 307 Temporary Redirect (since HTTP/1.1)
  In this case, the request should be repeated with another URI; however, future requests should still use the original URI.^[2] In contrast to how 302 was historically implemented, the request method is not allowed to be changed when reissuing the original request. For instance, a POST request should be repeated using another POST request.^[11]
  
  
• 308 Permanent Redirect (approved as experimental RFC)^[12]
  The request, and all future requests should be repeated using another URI. 307 and 308 (as proposed) parallel the behaviours of 302 and 301, but do not allow the HTTP method to change. So, for example, submitting a form to a permanently redirected resource may continue smoothly
  [/l][/l]

Beh la semplicità non è di questo mondo e non và mai d'accordo coi risultati che vorremmo ottenere.