Resources or Resource Buildings are used to get either one of the four main resources(Gold, Wood, Food and Stone). Without Resource Buildings it would be basically impossible to obtain Food which is needed to get Units.
Buildings
Gold:
-Gold Mine I/II/III/IV
Wood:
-Lumber Mill I/II/III/IV
Stone:
-Stone Mine I/II/III/IV
Scuddyman (talk) 08:16, May 22, 2013 (UTC)