3xx When a URL is moved from one location to another. Most often... More. This class of status code indicates the client must take additional action to complete the request. Many of these status codes are used in Uniform Resource Locators are the locations or addresses for... More When a URL is moved from one location to another. Most often... More. A user agent may carry out the additional action with no user interaction only if the method used in the second request is GET or HEAD.