The population unit is the base unit for all other units. The rate at which population grows at any given colony. The growth rate is dependent on the difference between the habitability of the system and the habitability of an empire's homeworld. A player's set of options for altering the look of the game system. Players maintain the same set of preferences across different games.
Production is allocated via spending.
It is fatal to enter any war without the will to win it. The amount of production generated by one population unit working for one turn. A profitable colony is one which generates more income than it requires for overhead. A colony with an agriculture greater than its overhead can be made profitable eventually when the population grows to its maximum. The technology that governs how far a ship can travel, in distance units, before needing to refuel.