Why the left of ship called port and the right starboard

Abstract

Ships transport about 90% of the global trade of goods and are the oldest and most popular means of transport in the international sale and purchase of merchandise. However, words and terms about ships are sometimes confusing for those who have worked in jobs related to this field. For example why use "she" only on a ship and not "he" or "it"; Why does the term "left" of a ship coincide with the word "port"), and "right" has the word "star" paired with "board" ? There have been many explanations for these questions, but so far it is not really convincing. Here are some explanations of the two words "port” and "starboard" for your reference.