Form
Form takes your design into the third dimension! Unlike shapes, forms have height, width, and depth (or at least create the illusion of depth on a flat surface). They're essentially 3D objects that exist in real or implied space.
Geometric forms include three-dimensional versions of shapes - cubes, spheres, cylinders, and pyramids. These structured forms appear in architecture, product design, and can create a sense of order in your compositions.
Organic forms include everything else three-dimensional, such as people, animals, and natural objects. These forms often have irregular contours and create a more natural, approachable feeling in your design.
Remember: You can create the illusion of form on a flat surface using shading, perspective, and overlapping elements. This technique helps transform simple shapes into forms with apparent depth.