Look around you. The lid of a jar, the bedroom door, a slice of pizza, the road sign: each one resembles a geometric shape. Flat shapes and non-planar shapes A shape is flat when it fits entirely on a sheet of paper, without “bulk”. A drawing in the notebook, the shadow of an object and the outline of a coin are flat shapes. A shoe box, a ball and a can are not flat: they have volume and take up space. But notice: the faces of the box are rectangles, and the lid of the can is a circle. Flat shapes are “glued” to the surface of objects.