Shapes and forms make up the outline of any two or three-dimensional object in a living space. Shapes are 2D and are viewed when looking at a schematic or an interior scene from one angle. Forms are 3D, made up of two or more shapes and accented by other design elements such as patterns or colours. Forms are the shapes you experience while moving around a space at different angles.
Well-defined forms create harmony and multiple forms balance a space. The two types of forms – geometric (man-made) and natural (organic) – can be categorized as open or closed. Open forms have surfaces that can be looked into whereas closed forms involve closed surfaces. Space and line are two design elements that must be used to achieve proper form.