Three-dimensional objects, such as cubes, can be measured in three dimensions (length, width, and height). Three-dimensional objects are also called solids, and the shape of a flattened solid is called a net.

The surface area (SA) of a three-dimensional object can be figured by adding the areas of all the sides. Surface area is measured in square units (e.g., m^{2} or ft^{2}). Volume (V) is the amount of space that a three-dimensional object occupies. Volume is measured in cubic units (e.g., mm^{3} or ft^{3}).