Despite the modern-day synonymy of "mariner" and "sailor", the term "mariner" originally held a higher rank in naval hierarchy. During the Age of Discovery in the 15th and 16th centuries, a "mariner" referred to an experienced sailor who was skilled in the art of navigation, drawing from knowledge about the sea, winds, the stars, and various navigation technologies of that era. They were essentially the GPS systems of the olden days! In contrast, "sailor" was a general term for anyone who went to sea, regardless of their skill level or responsibilities on the ship. So, if you were in charge of navigating a ship across the treacherous, uncharted oceans, you would proudly call yourself a mariner, not just a sailor.