Resource Units and the Bank

RESOURCEs are measured in FRUs: ``fundamental resource units''. Each player has a RESOURCE BANK that records how much of each type of RESOURCE a player has at the current moment. E.g., at some time, a player's BANK might record that she has 3 FRUs of wood, 5 of food, and 0 of iron. Every time a UNIT harvests an FRU of of some RESOURCE type, the corresponding bin in that player's BANK is incremented. Every time the player constructs a new UNIT or BUILDING, the corresponding bin is decremented by the necessary cost.