This document discusses 3D printing in architecture and structures. It begins with an introduction to 3D printing and additive manufacturing, describing how 3D printers build three-dimensional objects by laying down successive layers of material based on a digital file. It then discusses some key aspects of 3D printing like extrusion deposition which extrudes plastics, and granular material binding which uses laser sintering of powders. The document emphasizes how 3D printing can reduce costs, decrease risks, and create new design opportunities compared to traditional manufacturing.