# Industry Mechanics
There are five main industries in the game:
* Resources
* Armor
* Weapons
* Food
* Materials
Every industry has a technological level which define which products can be produced in the companies belonging to the industry.
Each industry is essential for a country's prosperity, however there is no way a country could develop all five industries to the maximum technological level. Thus, every country will have to choose in which industries its citizens should specialize, in order to produce the most valuable products.
The Industry level can be increased by earning experience points in skills that belong to an industry. However, only the 5 latest periods (1 period = 1 week) of earned experience points are taken into account.
In order to maintain the desired industry level, citizens must invest their energy in activities that give experience points, such as studying or working.
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