These buildings are those that are neither offensive, defensive, or resource-giving. However, they are just as critically important. The Town Hall, for instance, is the heart of the village and regulates what buildings you can have, how many of them you can have, and how far you can upgrade them. The Clan Castle, on the other hand lets you connect with other players in a clan. Decorations are there to decorate your village. Obstacles are trees and rocks which can be found in your village. Clearing them will sometimes gives you Gems.
Learn about the various other buildings in Clash of Clans by clicking on one of the images below.