The other vessel is coming directly toward the observer, so both the port and starboard running lights are visible.
You are approaching the stern of another vessel
You are approaching the starboard side of another vessel
The other vessel is coming directly toward the observer, so both the port and starboard running lights are visible.
You are approaching the stern of another vessel and may be overtaking it
A visible white light on another vessel indicates that it is approaching you head-on. This means you should also exhibit a white light to signify that your vessel is also approaching head-on.
A visible white light indicates that the other vessel is a power-driven vessel.
You are approaching the stern of another vessel
In darkness or reduced visibility, visible red and green lights on a vessel indicate its orientation and direction of travel. A steady red light on the port (left) side and a steady green light on the starboard (right) side signify that the vessel is underway and facing the observer. If you see both red and green lights, it means you are approaching the bow of the vessel. If only one light is visible, it indicates the vessel's side, helping you assess its direction and take appropriate navigational actions.
You are approaching the port side of another vessel
Give-way to starboard side
3 seconds of rapid bell ringing
It depends on the configuration seen. There are different lights visible depending on the relative headings of the vessels and relative sizes etc.