Edgar Rubin’s Vase, 1915
This is an example of both positive and negative shape. The positive shape would be the vase, and the negative shape would be the two faces. Positive shapes are your figure or your subject, whereas negative shape is your ground or background.
Ernst Haeckel (Title, media, date, all unknown), Image Source
“Organic shapes are figures that have a natural look and a flowing, curving appearance. Different from geometric shapes, they are often also referred to as curvilinear or free form shapes, as they can be made of angles, curves or both. Examples are found in leaves, plants, and animals.” – http://www.wisegeek.org
Piet Mondrian, Composition with Yellow, Blue, and Red, 1937–42, oil on canvas
A geometric shape is one that follows the rules of geometry that mainly follows angles and curves. They create shapes that can accurately be measured. This example shows that simple shape like the rectangles and squares can still make an interesting and intriguing work of art.