3D printing turns computer models into real physical things. It takes different materials, from biodegradeable plastic filament PLA to ABS plastic to Nylon, melts it into thin layers onto a surface, moves up and prints another layer. After layer upon layer, you are left with a physical object
To prepare the digital file created in a 3D modeling program for printing, the software slices the final model into hundreds or thousands of horizontal layers. When this prepared file is uploaded in the 3D printer, the printer creates the object layer by layer. The 3D printer reads every slice (or 2D image) and proceeds to create the object blending each layer together with no sign of the layering visible, resulting in one three dimensional object.