It isn't. It's more commonly on the right side.
Facing forward, starboard is the right side of the boat. (the steering board (rudder) used to go on the right, so the left side was the port side)
BITD boats didn't have rudders in the center, but side-hung rudders. For some reason, it became tradition to "always" put the rudder on the right side of the boat. "Right" on boats is called "starboard" - the side where the steering board was. When entering a port, people tied up with the rudder facing OUT, to avoid damage. So left became "port", from portside. Staying with tradition from the old side-hung rudders, steering is done from the right, starboard side of the boat.
Comes from old English from Sterobord, as the old boats used to have the steering rudder on the Right side of the boat. Port side came from the same with the Steering rudder on the right ships would dock on the left side as not to damage the steering rudder.
On a boat, the right side is the starbord side; the left side is called port.
Wales have left-side traffic and right side steering.
The right side of a boat is the starboard.
If a person is in front of a bow( Front side of a boat) right side is starboard.
If a person is in front of a bow( Front side of a boat) right side is starboard.
Right hand side of the steering column.Right hand side of the steering column.
When facing forward, the right side of the boat is 'starboard', and 'port' is toward the left.
The right side is starboard