Three-dimensional figures include objects such as pyramids, prisms, cones, cylinders, and spheres.  We often call three-dimensional figures solids.

When working with two-dimensional figures, such as quadrilaterals and circles, we can find area and perimeter.  With three-dimensional figures we can find volume or surface area.

We can "unfold" a solid to get its net, which is a flat, two-dimensional view of the object.  Finding nets can help us visualize the solid as well as assist us in finding surface area of the solid.