During night navigation, from sunset to sunrise, or in restricted visibility (fog, falling snow, heavy rainstorms, etc), by displaying the appropriate lights, other craft will know if your craft is under sail, power driven, or at anchor. Large ships, vessels with fishing nets, and tugboats pulling barges will display additional lights so that they can be identified as such. As well, during night navigation, it will be possible to determine who has the right-of- way when two craft meet by looking at the colour of the other craft's navigation lights.
Sidelights: a red light on the port side and a green light on the starboard side, each displaying a constant beam and affixed in a manner that the light is projected to the front and sides allow you to determine if the oncoming craft is heading towards you or from one side or another.
Sternlight: a white light placed as closely as practical at the stern shining constantly, affixed in a manner so that the light will shine out at 135 degrees from the back of the boat and affixed to show the light from aft on each side of a pleasure craft.
Masthead light: a white light placed over the fore and aft centreline of a pleasure craft shining constantly and affixed to show the light from straight ahead to either side of a pleasure craft.
All-round light: a white light shining constantly over the horizon at an arc of 360 degrees.
Blue flashing light: attributed to all law enforcement agencies and some government agencies, emitting an all-around blue-flashing beam engaged in duties in Canadian waters.
Special flashing light: a yellow light placed at the forward end of a towing vessel or vessel being towed.