. Fixed (or collapsible): The sheet opens by rotating on the vertical axis;
. Abatible (horizontal rotation): The leaf opens rotates on a horizontal axis;
. Oscilobatente: It allows the leaf to open in two ways, combining the previous two;
. Pivoting aperture: Leaf rotates around a central axis, usually horizontal;
. Foldout: The leaves collapse against one side of the opening.