This document discusses the possibilities and benefits of 3D printing. 3D printing allows anyone to design and create physical objects by printing layer by layer. It enables rapid prototyping and manufacturing of custom parts at low costs. The document highlights how 3D printing is used today in fields like medicine to create prosthetics and will someday print human tissues. It notes that 3D printing costs a few dollars per part while traditional manufacturing methods can cost thousands of dollars for molding. The document envisions a future where 3D printing is used to print parts of a space station.