3D PRINTING ADDITIVE MANUFACTURING AND ITS TYPES Introduction 3D printing, or additive manufacturing, is the construction of a three-dimensional object from a CAD model or a digital 3D model. A CAD model allows someone to see a part in three dimensions, including any intricate features that would be difficult to depict in a two-dimensional drawing. The term "3D printing" can refer to a variety of processes in which material is deposited, joined, or solidified under computer control to create a 3D object, with the material being added together (such as plastics, liquids, or powder grains being fused together), typically layer by layer. Processes of Additive Manufacturing Modeling 3D printable models may be created with a computer-aided design (CAD) package, via a 3D scanner, or by a plain digital camera and photogrammetry software. CAD models can be saved in the stereolithography file format (STL), a CAD file format for additive manufacturing that stores data based on tri