A 3D printer is a computer-aided manufacturing (CAM) device that creates three-dimensional objects. Like a traditional printer, a 3D printer receives digital data from a computer as input. Instead of printing the output on paper, a 3D printer builds a three-dimensional model out of a custom material.

3D printers use a process called additive manufacturing to form (or “print”) physical objects layer by layer until the model is complete. This is different than subtractive manufacturing, in which a machine reshapes or removes material from an existing mold. Since 3D printers create models from scratch, they are more efficient and produce less waste than subtractive manufacturing devices.

The process of printing a 3D model varies depending on the material used to create the object. When building a plastic model, a 3D printer may heat and fuse the layers of plastic together using a process called fused deposition modeling (FDM). When creating a metallic object, a 3D printer may use a process called direct metal laser sintering (DMLS). This method forms thin layers of metal from metallic powder using a high powered laser.

While 3D printing has been possible since the 1980s, it has been primarily used for large scale industrial purposes. However, in recent years, 3D printers have become much cheaper and are now available to the consumer market. As the technology becomes more widespread, 3D printers may become a viable means for people to create their own home products and replacement parts.