Diferencia entre offset y letterpress

Many years ago I asked my teacher , “What is difference between letterpress and offset printing?” He said, “Come forth young lass, and I will show you.” As I approached his desk, he pulled out his hankie, kissed it, then touched my cheek with it, “this is offset printing.” “Now let me show you letterpress.” At that point he threw the hankie down and proceeded to kiss me directly on the face and said, “That is the difference.”
(visto en Briarpress.org)