When encountering other vessels in the dark or reduced visibility what do visible white lights indicate?

In the dark or reduced visibility, visible white lights on other vessels indicate the presence of those vessels and their orientation. A white light typically signifies the stern or the all-round light, helping to determine the vessel's heading and whether it is underway or at anchor. The specific configuration and type of white lights can provide additional information about the size and nature of the vessel. Observing these lights is crucial for safe navigation and avoiding collisions.