Hinge for hanging doors. A butt hinge is a type of furniture hinge that is commonly used in cabinet doors, interior doors, and other furniture applications. It consists of two rectangular metal plates, one attached to the door and the other to the frame, which are connected by a pin. The term butt refers to the fact that the hinge is mounted on the surface or butt of the door and frame, rather than being recessed into the wood. Butt hinges are known for their simplicity and durability and are often used in traditional and classic furniture styles.