What are the functions of lighthouses, water towers and signal towers?

As a navigation mark, lighthouse is used to mark coastline, dangerous objects and turn lights. With the development of modern navigation AIDS, they are not limited to lighthouses, but also include light ships, light piles and light buoys. The identification type is not limited to visual lighting, and the development of radio navigation equipment is changing with each passing day, and even AIS virtual navigation AIDS accepted by special radio equipment have appeared. The functions at home and abroad are basically the same, but with the development of science and technology and the large-scale ships, many lighthouses with a long history have become places of interest and gradually lost their navigation AIDS. As for how to realize the function, each lighthouse will have its own unique light color and flashing rhythm, so as to distinguish it from the adjacent lighthouses, so that sailors can observe the light quality and rhythm at night, compare it with the lighthouses marked on the chart, and then judge whether their position is yaw and safe according to the compass orientation relative to the lighthouses. In this way, the lighthouse plays a role in ensuring the safety of ships and assisting navigation.