An icon case or kiot is a decorated case (usually foldable) or glass shelf for keeping and displaying religious icons. Icon cases range in size and design. Common Greek kiots are tall and typically carved wood. They can be ornate or simple. They resemble windows with a roof or dome on top, and therefore support the Orthodox Christian theology of icons as "windows into heaven". The icon usually is placed vertically rather than at an angle as on analogion. Sometimes, there may be a secondary icon on a slanted shelf below the main icon. Some Greek kiot also have a step or platform so that veneration of the icon is easier.