For sailors, the terms port and starboard are nothing new — in fact, they are considered essential knowledge. These are English terms that refer to the left and right sides of a ship.
But have you ever wondered why these terms are fixed as such in English, rather than simply saying left-hand side and right-hand side?

First of all, one of the key reasons why "left" and "right" are not used in maritime language is to avoid confusion about direction. Words like "left" or "right" are relative, and depend on a person’s orientation — which side they’re facing. In situations where precision is critical, such ambiguity could lead to dangerous mistakes.
To ensure clarity, in addition to using compass bearings and coordinates, sailors also rely on fixed directional terms: port for the left side of the ship, and starboard for the right side.

So why specifically starboard and port — and not some other terms?
To answer that, we need to travel back to the Middle Ages, when maritime navigation was flourishing in Northern Europe, home to the legendary Viking seafarers.

At that time, ships didn’t have a central rudder like modern vessels do. The only way to steer the ship was by using a large steering oar, which was fixed to the right-hand side near the stern of the vessel. Since most people are right-handed, this side was easier and more natural for steering.

In the old Nordic languages, the term used for steering oar sounded very similar to the English word “star”. The Anglo-Saxons later adopted this term from the Vikings, and called the right-hand side of the ship “starboard” — literally meaning “steering side”.

Because the steering oar was permanently mounted on the starboard side, ships had to dock with their left side facing the port to avoid damaging the steering gear.
This side naturally became known as the “port” side, a term that has remained in use ever since.