Fused Deposition Modeling
FDM is the most common 3D printing method used in desktop 3D printing. Thermoplastic filament is heated and extruded through an extrusion head that deposits the molten plastic in X and Y coordinates, while the build table lowers the object layer by layer in the Z direction.
Effectively, the object is built from the bottom up. If an object has overhanging parts, however, it will need support structures that can be removed after the printing is finished.
This type of 3D printers is a cost-effective means for product development and rapid prototyping in small business and education sectors since it’s capable of fabricating robust parts reliably and quickly.
Source : all3dp.com