A ship officer is a person responsible for the operation and navigation of a vessel. The four main officers on a ship are the SKIPPER, MATE, BOSUN, and PURSER. The SKIPPER is the captain of the ship and is in charge of the overall operation and navigation of the vessel. The MATE is the second-in-command and assists the SKIPPER with navigation and other duties. The BOSUN is the head of the deck crew and is responsible for the maintenance and upkeep of the ship. The PURSER is the head of the administrative staff and is responsible for the financial and personnel management of the ship.