Ships' officers are responsible for the navigation, operation, and maintenance of a vessel. The two most common positions are EXECS (5 letters) and MATES (5 letters). EXECS are the highest ranking officers on a ship and are responsible for the overall management of the vessel, including its crew and cargo. MATES are second in command and are responsible for the day-to-day operations of the vessel, such as navigation, maintenance, and safety.