Cabin person is the lowest rank a player can have in a crew as a full member of that crew. Players are assigned the rank of cabin person automatically when they join a crew. Aboard ships, cabin people can only play the bilging, patching, carpentry, rigging and sailing puzzles, unless an officer (or above) gives them an order.
On subscriber oceans, players are often promoted to pirate once they have subscribed. On doubloon oceans, many crews promote cabin people to pirate or above, immediately upon becoming full members of the crew. For these crews, the cabin person rank is reserved as a disciplinary measure. Each crew has different requirements for promotion.