3D printing is a process that creates three-dimensional objects from a digital file by depositing material layer by layer. It allows for quick production of customized objects without the constraints of traditional manufacturing. The most common type of 3D printer uses fused filament fabrication, which heats and extrudes plastic filament through a nozzle to build an object layer by layer. 3D printing offers advantages over conventional manufacturing like low-cost production of customized goods and on-demand creation without logistics.