Before you can print an object, you need a digital model of that object to work from. An object can be scanned in real life and then imported into the computer, or an entirely new object can be created with the help of CAD (computer-aided design) software. The digital model effectively serves as a blueprint for the printer, showing the exact size and dimensions of each part of the object. When finished, the design will be converted into an .STL file (for “stereolithography” or “Standard Tessellation Language”). Converting the object to .STL will divide it into cross-sectional slices, which are used by the printer to build up the object, layer by layer.