Port and starboard are nautical terms used to refer to the left and right sides of a vessel, respectively, when aboard and facing the bow (front) . These terms are used instead of left and right to avoid confusion, as port and starboard never change and are unambiguous references that are independent of a mariners orientation.
The term "starboard" comes from the Old English word "steorbord," which means the side on which the ship is steered. Before ships had rudders on their centerlines, they were steered with a steering oar at the stern of the ship on the right-hand side of the ship, because most people are right-handed. Sailors began calling the right side the steering side, which soon became "starboard" by combining two Old English words: stéor (meaning "steer") and bord (meaning "the side of a boat") .
The left side of the ship was originally called "larboard," but this was easily confused with "starboard," especially when challenging conditions at sea made it difficult to hear. The switch was made to lead to a distinctive alternate name. The old English name for the port side sounded like "backboard," and on big vessels, the sailor using the steering would have his back facing the ships left side. As a result, "backboard" was named "laddebord," which is the loading side of the ship. Later, "laddebord" became "larboard," causing the confusion that led to the change to "port".
In summary, "starboard" refers to the right-hand side of a vessel when facing the bow, and "port" refers to the left-hand side of a vessel when facing the bow. These terms are used instead of left and right to avoid confusion, as they are unambiguous references that are independent of a mariners orientation.
