The manpower distribution in seagoing vessels is essentially organised in something known as the ship organization chart based on position and responsibilities.
For all practical purposes, all shipboard operations are divided into three main heads:
- Deck Department
- Engine Department
- Catering and hospitality
The deck department is the most important division that deals with the vessel’s navigation, cargo (along with loading, handling, and unloading), docking, seakeeping and manoeuvring, stability,...
https://www.marineinsight.com/marine-navigation/understanding-a-ship-organisation-chart/