A window shutter is a solid and stable window covering usually consisting of a frame of vertical stiles and horizontal rails (top, center and bottom). Within this frame can be set louvers (both operable or fixed), solid panels, glass, fabric, and virtually any other item that can be mounted within a frame. Shutters may be installed for any number of reasons including to provide privacy, controlling the amount of sunlight that enters a room and to protect against weather. Depending on the application, and the construction of the window frame, shutters can be mounted to overlap the opening or fit within the opening. The term window shutter applies to many types of coverings including both interior and exterior shutters, used on the inside of a house or building, and exterior shutters, used on the outside of a structure. On some styles of buildings it is common to have decorative iron shutters to cover the doors as well as the windows.