The German printer Johannes Gutenberg is generally credited with inventing the modern printing press about 1440. A printing press is a device for applying pressure to an inked surface resting upon a print medium (such as paper or cloth), thereby transferring the ink. Typically used for texts, the invention of the printing press is widely regarded as one of the most influential events in the second millennium, ushering in the period of modernity. Gutenberg, a goldsmith by profession, devised a hand mold to create metal movable type, and adapted screw presses and other existing technologies, to create a printing system. The mechanization of bookmaking led to the first mass production of books in Europe. A single Renaissance printing press could produce 3,600 pages per workday, compared to about 2,000 by typographic block-printing prevalent in East Asia, and a few by hand-copying. Books of bestselling authors like Luther or Erasmus were sold by the hundreds of thousands in their lifetime.

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