How Does 3D Printing Work?

Also called additive manufacturing, 3D printing starts with a digital 3D model that is "sliced" by software into hundreds or thousands of thin horizontal layers. The printer then builds the object from the bottom up, adding one layer at a time. In FDM (Fused Deposition Modelling), a heated nozzle extrudes thermoplastic filament; in SLA (Stereolithography), a UV laser cures liquid resin; in SLS (Selective Laser Sintering), a laser fuses powdered material. After all layers are deposited, the object is complete, often requiring minimal post-processing. 3D printing is used in prototyping, medicine (custom implants), aerospace (rocket engine parts), construction, and even food preparation.