Well before Gutenberg's development of printing from movable types, a great deal of printing on paper by woodcut had been done. Perhaps the most popular form of this kind of block printing of text and image had been in the form of the Biblia Pauperum, or Bibles of the Poor. Printers in this woodcut sense preceded typographic printers, though by just how long a period it is not easy to establish, because these cheap and popular prints, despised by the learned, were not preserved any more than are the comic books of today. The great law of bibliography comes into play in this matter of the printing that precedes Gutenberg: "The more there were, the fewer there are." It applies to many items besides printed matter—to the postage stamp and to the early forms of radio receiving sets.