Complex sentence: FDM works on an "additive" principle by laying down material in layers; a plastic filament or metal wire is unwound from a coil and supplies material to produce a part.FDM is a solid-based additive manufacturing (AM) technology.
Split into simpler sentences: FDM works on an "additive" principle by laying down material in layers; a plastic filament or metal wire is unwound from a coil and supplies material to produce a part. Thus, FDM is also known as a solid-based additive manufacturing (AM) technology.