3xx - Redirection
300 (Multiple Choices)
Due to duplicate filenames or word sense disambiguation (where the exact meaning cannot be determined) more than one choice of resource is possible. Generally this is dealt with in one of two ways - an assumption is made (for example; lets just take the first resource in order of age), or a choice is provided to the client (please choose).
301 (Moved Permanently)
This resource has been moved and it's new location will be its new permanent location, all future requests should be made to the new location.
Previously "Moved Temporarily"; this resource is currently at a different location, however this may change and so this location should be used for the time being until a permanent location is found, and a 301 issued.
303 (See Other)
As with 302, the requested resource has moved, the resource can be fetched from the new location using a GET request.
304 (Not Modified)
This resource has not changed since the last request from this client, a cached copy should be used.
305 (Use Proxy)
The requested resource must be accessed through the proxy given by the location field.
306 (Switch Proxy)
The 306 code is no longer in use.
307 (Temporary Redirect)
Continue to use this location for theis resource, however at this time you will be redirected.