Two-dimensional (2D) shapes are completely flat. They cannot be picked up. A polygon is a 2D shape with straight sides that meet at vertices. Polygons have names that show the number of sides they ...

The growing popularity of 3D printers, such as the Printbot or MakerBot's Thing-o-Matic, testify to the fact that additive manufacturing is slowly entering the mainstream. The devices are now small ...