If you ever were a kid around water or have simply visited a swimming pool in the last decade, chances are you have heard kids yelling the words, “Marco” and “Polo.”

The games kids (and sometimes adults too, depending on the atmosphere and the consumption of certain beverages) play seem to be passed down from generation from generation like a family recipe. But a lot of the origins of the games have been lost, and now children are seen yelling names and going through the motions without ever knowing the who and the why.

Understanding the etymology of swimming pool activities won’t make the games themselves any more fun, but it could help you settle an argument or help you do well when the next trivia game is brought out pool side.

One the of the most famous pool games of all time is “Marco, Polo.” It has endured the test of time because you don’t need any equipment and anyone can play. It’s basically “hide and seek” with your eyes closed and in water. One person closes their eyes, and says, “Marco.” The other people in the pool yell back, “Polo,” and the visionless swimmer attempts to use sound to locate and tag the other swimmers.

A few things of note surrounding the game. One, Marco Polo is one man, not two. Polo was an explorer from the 13th Century whose book helped the rest of Europe get to know Central Asia and China. Two, the game was created “tongue n’ cheek.” The navigational kids’ game was created to poke fun at Polo, who historians say was mocked for constantly not knowing where he was or where he was going. As if he was going through the waters with his eyes closed.