The invention of printing was a revolutionary development that brought about profound social change in Europe in the fourteenth and fifteenth centuries. A. Printing with metal type rather than woodblocks was the invention of a German goldsmith living in Rome, the center of printing in the fifteenth century. B. A precondition for the successful production and distribution of mechanically printed books was the earlier commercial organization of hand-copied book production by merchants known as stationers. C. Because movable type made it more economical to produce many copies of a single book, the invention of mechanical printing had an immense effect on the spread of knowledge. D. The expansion of the paper making industry in the fourteenth and fifteenth centuries made it possible to fully and economically use the invention of movable type in book production. E. In the fifteenth century, printed books were internationally distributed through the Frankfurt book fair, although few people in the fifteenth century could afford books or were able to read them. F. The most important and expensive early mechanically printed book was Gutenberg's two-volume Latin Bible, produced in an edition of only 185 copies.