Form is defined as the overall 3D geometric shape of the design that can be measured by height, width and depth.
When looking at a design, you should be able to see a distinctive shape to the design. These include circle, square, rectangle, oval, triangle, crescent, etc.
You may also see a "Free Form", however, this is not a shape, but an interpretation or extension of a form and should only be done when the basic forms are mastered. Forms can either be open or closed.
Open form: light and airy and has space between the materials.
Closed form: a tight or massed placement of materials with little or no space between each item.
You can download a 24"x36" PDF poster, a worksheet and a printable of this visual on the TSFA Member's Only Info Hub.