What is bulwark on a ship?

A bulwark on a ship is a protective barrier or wall that is installed along the edge of the deck to prevent water from reaching the deck and to protect the crew and cargo from rough seas. It is usually made of metal or wood and can be raised or lowered depending on the weather conditions. The bulwark also helps to provide structural support to the ship's hull. The top of the bulwark is called the rail, and it provides a handhold for the crew when working on deck. The bulwark serves as an essential safety feature on a ship and is an important part of its design.