The industry descriptions:

Agriculture

Agriculture industry grows the food for the colony

Armaments

Armaments factories builds the weapons for ships

Basic_Industry

Basic Industry builds the equipment for the other factories

Civilian Factories

Civilian Factories creates consumer goods which influences the happiness of the colony

Construction

Creates houses for both civilians and troops on the colony

Government

The civilian government that runs the colony and collects your taxes.

Mining

Mines the minerals and metals on the planet based on the metal rating.

Unemployment

When there is not enough capacity in an industry these people are displaced and collect unemployment wages.