Buildings
Army Buildings
The Army Buildings are any buildings related to the the troops and spells used to invade in Clash of Clans. This includes any buildings with the purpose of creating, housing and upgrading the troops and spells.
Defensive Buildings
The Defensive Buildings are any buildings related to the defense of your base, and serve the purpose of attacking invaders from destroying your base, and protecting the resources within your base.
Resource Buildings
Resource Buildings are buildings related to the production and storage of resources. These resources are whats used to create and upgrade all troops, buildings and spells in Clash of Clans. Additionally they can be used to remove obstacles. The only substitution for resources is gems.
Other Buildings
The other buildings in Clash of Clans serve unique purposes.