Picture this. You are twenty-five meters below sea level, exploring a long coral reef, beautiful brain corals and webbed fans sway in the ocean currents. A few meters in front of you, you saw a sea turtle nab a jellyfish, chewing languidly as it glided smoother than any human could. A picturesque scene if there ever was one, right? Suddenly, something flashes across your vision and you twist around to see what it is. Thankfully, it's only your buddy, having been looking the other way while watching a school of fish. They look at you, head tilted slightly, and bring up a hand, pinching the thumb and forefinger. They're asking if you are okay. You bring up the same sign with your own hand, signaling that yes, you are fine and dandy. In fact…

https://www.caradonna.com/blog/scuba-signs-safe-underwater-adventures