That’s where 3D printing has a niche.” So how, exactly, does a 3D printer work? What is 3D printing? Consider the type of printing most people are very familiar with: Printing with ink on paper.

Yes, 3D pens really work, if what you want to do is create a 3D model by hand. If you want to create a 3D model based on a pre-existing design, though, you need a 3D printer.