Food
Produced at Farms, Food is mainly used for troop training.
Wood
Produced at Mills, Wood is mainly used for construction and siege unit training.
Stones
Produced at Quarries, Stone is used for building and upgrading defensive structures.
Pennants
Produced at Cathedrals and Universities, Pennants are used for researched technologies and unlocking Unique Units.
Gold
The premium resource, Gold can be used to speed up the building and training.