- 200 (OK): This response code is returned if the document or file in question is
found and served correctly.
- 304 (Not Modified): This response code is returned if a browser has indicated that it has
a local, cached copy, and the server’s copy has not changed from
this cached copy.
- 401: (Unauthorized): This response code is generated if the request in question requires
authorization to access the requested document.
- 403 (Forbidden): This response code is returned if the requested document does not
have proper permissions to be accessed by the requestor.
- (404 Not Found): This response code is sent back if the file that is attempting to be
accessed could not be found (e.g., if it doesn’t exist).
- 500 (Internal Server Error): This code will be returned if the server that is being contacted has a
- 503 (Service Unavailable): This response code is generated if the server is too overwhelmed to
handle the request.