FDM - fused deposition modeling - this is what most people think about (at least what I do) when it comes to 3D printing. You have a filament of material, melt and extrude it.
SLA - Stereolithography Apparatus - I am not going to do this. This is where you have a tank of liquid and UV light cures layer by layer. You have to deal with weird liquids and their handling and disposal.
Adventures in Computing / tom@mmto.org