To become acquainted with the latest significant changes to lights and fog signals, e.g. light vessels, light structures, light buoys, etc., you have to consult the List of Lights and Fog Signals or the Yachtsman’s Almanac. These publications provide you with detailed changes. Since up to 17 months may elapse between publications, Notices to Mariners should be consulted for up-to-date information. These Notices supply you in the meantime with any changes that may have occurred. Notices to Mariners also provide you with other recent information such as chart corrections, navigational warnings etc.