Chapter 1 describes 3D printing technology’s capabilities and its limitations. It also explains the important concept of physitization, which is the term I use to describe the bidirectional path that 3D printing creates between physical and digital versions of objects. At the industrial level, 3D printing technology catalyzes new methodologies for product design, development, and production, and it lowers the cost and weight of an array of existing products. At the personal level, 3D printing technology democratizes design and manufacturing, opening doors to widespread product innovation, free and open source collaboration, and artistic creations. At both the industrial and individual levels, the technology dramatically lowers the costs of product design and commercialization and ushers in an era where a product’s complexity of shape is not a barrier to manufacturing.