A shape is flat. It has height and width, like a circle cut from paper. A form is solid. It has height, width and depth, like a ball. You met shapes in the Young Artists course; now each one grows into a form.
| Shape (flat) | Form (solid) | In the world |
|---|---|---|
| circle | sphere | an orange, a ball |
| square | cube | a sugar cube, a die |
| triangle | cone | a party hat, a traffic cone |
| rectangle | cylinder | a can, a pencil, a tree trunk |
Key idea
A shape has height and width. A form has height, width and depth. Circle to sphere, square to cube, triangle to cone, rectangle to cylinder.
Why it works
Almost every object can be built from a few forms, so if you can draw these four, you can start almost anything. Two tools turn a flat shape into a form on paper: lines that show depth (like the ellipse at the top of a can) and shading that shows light turning across the surface.
Worked example: An orange
You draw a circle for an orange. What makes it read as a sphere instead of a flat circle?
- A circle is a shape; it has no depth.
- Shading from light to dark across it, a highlight and a cast shadow show that it is round and solid.
Answer: Shading: light on one side, shadow on the other, and a cast shadow.
Worked example: Name the form
A drinking straw: which form?
- It is long and round, with circles at each end.
Answer: A cylinder.
Common mistake
People often use "shape" and "form" as the same word. In art, a shape is flat and a form is solid. A square drawn on paper is a shape; a box you could hold is a form.