Under Japan's recently revised immigration laws, foreign residents of the country are explicitly instructed to inform the Ministry of Justice Immigration Bureau of any changes to information they've registered with the bureau. For example, when you change jobs or get a divorce, you're now required to notify the immigration bureau and can face penalties for failing to do so.
To ease the burden of these notifications, the Immigration Bureau has established an online notification service that allows foreign residents to log in and submit many (but not all, as we'll see) of the legally required notifications without making a time-consuming and, for some, costly visit to the nearest regional or branch office.