Markforged Desktop 3D printers utilize a 3D printing technology called Fused Filament Fabrication (FFF) and CFF (Continuous Filament Fabrication).  FFF is the most common and affordable type of 3D printing — most machines utilize this technology. In FFF, the printer heats up thermoplastic to near melting point and extrudes it out a nozzle that traces the cross section of a part for each layer. This process repeats for each layer.  CFF is an augmented FFF process that works in addition to an FFF printer to lay continuous fiber in a part. In this process, a printer utilizes a second nozzle to lay continuous strands of composite fibers inside a convention FFF thermoplastic parts. Parts built with the CFF/FFF process are strong and stiff due to their reinforcing fibers.