What is shape?

Shape is what can be described verbally to describe an object. Vocabulary of shapes are pretty limited. Some examples are spherical, cylindrical, cuboid, flat, round, convex, concave, ring, torus, conical. Complex design can be made by combining two or more shapes in a legible manner, so as to create different feeling. If one notices carefully the shapes can be defined by relatively simple mathematical equations or functions. Let us call those surfaces the Slabs surfaces or Base surfaces. If we were to list down the characteristics of the base surfaces, they would be as follows.

Can be described verbally.
simple mathematical equations.
uniformity of curvature.

What is Form?

Form can be defined as a collection of basic shapes. It can be made more complex by creating transitions from one basic shape to another. Common forms of transition are fillet and chamfers. In some complex form the transition surface can engulf the base surfaces or primary surfaces in its entirety.  There can be different levels of "smoothness" by which the transition surfaces blends the primary surfaces. The common fillet can be described as the surface defined by a ball if it rolls between two primary surfaces.