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Johannes Gutenberg of Mainz, Germany, invented the printing press, using a metal movable type system. Gutenberg, as a goldsmith, knew techniques of cutting punches for making coins from moulds. Between 1436 and 1450 he developed hardware and techniques for casting letters from matrices using a device called the hand mould.[3] Gutenberg's key invention and contribution to movable-type printing in Europe, the hand mould, was the first practical means of making cheap copies of letterpunches in the vast quantities needed to print complete books, making the movable-type printing process a viable enterprise.[citation needed]