Relief: The printing surface is above the rest of the block, which has been chiseled away. Ink is applied to this raised surface and printed using vertical pressure.
Intaglio: The design is incised into a metal plate, which is wiped clean after inking, leaving the ink in the incisions. This means the plate need to be printed under great pressure in order to push the paper into contact with the ink. The pressure of the printing press usually leaves a characteristic plate-mark on the print, where the plate has indented the paper.
Planographic: Printing process where there is no difference in level between the inked and non-inked surfaces.