Red doesn't mean just "war" and, in anticipation of Valentine's Day, a beating heart. In the International system, navigation aids mark the edges of channels to tell which way open water is. They are called day beacons if unlighted, lights if lighted at night, or buoys if they are floating. Some buoys are also lighted for identification at night.
"Red, Right, Returning" tells you to leave the red markers to your right, or starboard, when returning from sea. The green markers are then left on your port side and between is the channel. Be sure to look behind you when navigating a narrow channel to make sure you are not being pushed out by wind or current.
Floating Red markers are called nuns and are triangular in shape. They are numbered with even numbers. Floating Green markers, on the other hand, are called cans and are square or shaped like a large can and carry odd numbers.
So the thought for the day is to keep to the middle, avoid the reds and perhaps the greens which are likely somebody's front lawn.
