A fog horn is a loud sound signal used primarily in maritime navigation to warn ships of nearby hazards, especially in foggy conditions. It helps vessels avoid collisions with land, other ships, or obstacles in the water. Fog horns can be powered by electricity or compressed air and produce a deep, resonant sound that travels over long distances. Typically installed at lighthouses or coastal areas, fog horns operate at regular intervals to ensure their signals are heard. They are an essential safety feature in areas prone to fog, enhancing the visibility of navigation points for sailors. Lighthouse and maritime navigation are closely related to the function of fog horns.