Ship's Crew
Crew roles and responsibilities aboard commercial vessels
Captain
The captain is a ship's highest officer, acting on behalf of the ship's owner. Department heads report to the captain who is ultimately responsible for the safety and security of the ship, and crew’s welfare in keeping with all maritime legal requirements.
Navigation officers
Deck officers, also known as mates, make important decisions on the navigation, communications, crew, cargo and overall running of the ship. They are also responsible for the safety of the crew, cargo, passengers and vessel both at sea and at port.
Chief mate
The chief mate is the head of the deck department and second-in-command. The Chief mate's primary responsibilities are the vessel's cargo operations, its stability, supervising the deck crew and directing bridge operations. Additional duties include maintenance of the ship's hull, cargo gears, accommodations, lifesaving appliances and firefighting appliances. The chief mate also trains the crew and cadets on board.
Second mate
The second mate is qualified to stand watch, direct the bridge team and navigating the ship. The Second mate's primary duty is navigational, which includes updating charts and publications, keeping them current, making passage plans, and all aspects of ship navigation. The Second mate's other duties may include directing line handlers, cargo watches, directing anchor detail and training and instructing crew members.
Third mate
The Third officer is a qualified to stand watch, direct the bridge team, and maneuver the vessel keeping it safe and on track. The Third mate's primary duty is matters of safety, inspecting gear lockers, lifeboats, and all equipment onboard ensuring that it is safe and operational. Other duties include directing line handlers, cargo watches, directing anchor details.
Deckhand
Deckhand complete tasks such as working mooring lines, operating deck gear, standing anchor details, and working cargo. They also stand navigational watch, generally as a lookout or helmsman.
Engineering officers
The engineers are also called technical officers. They are responsible for keeping the ship and the machinery running. Today, ships are complex units that combine a lot of technology within a small space. This includes not only the engine and the propulsion system, but also, for example, the electrical power supply, devices for loading and discharging, garbage incineration and fresh water generators. Also they are commonly considered a high officer in ranking in the ship.
Chief engineer
The chief engineer head of the engine department, responsible for keeping the ship and machinery running. This includes not only the engine and the propulsion system, but also, electrical power supply, loading and discharging devices, waste incineration and freshwater generators. They also oversee operations and maintenance of machinery and equipment throughout the ship.
Second engineer
The second engineer is the officer responsible for supervising the daily maintenance and operation of the engine department.
Third engineer
The third engineer is usually in charge of boilers, fuel, auxiliary engines, condensate and feed systems. They may also be in charge of fueling, with a Person In Charge (PIC) endorsement for fuel transfer operations.
Fourth engineer
The fourth engineer assists the third and second engineer with engine room duties.
Electro technical officer
The electro-technical oversees all electrical systems on board ship. Their duties include carrying out electrical and electronic maintenance, repairs, installations and testing.
Ship’s cook
The ship’s cook responsibilities include planning menus, preparation of meals, and ordering supplies and ensuring their proper storage. They are also in charge of maintaining cleanliness of the galley.
Source:
https://en.wikipedia.org/wiki/Seafarer%27s_professions_and_ranks