The most important aspect of his invention was that it was the first form of printing to use movable type.
His initial efforts enabled him in 1440 to mass-produce indulgences – printed slips of paper sold by the Catholic Church to remit temporal punishments in purgatory for sins committed in this life, for those wealthy enough to afford indulgences. Gutenberg’s invention spread rapidly after his death in 1468. It met in general with a ready, and as enthusiastic reception in the centers of culture. The names of more than 1000 printers, mostly of German origin, have come down to us from the fifteenth century. In Italy we find well over 100 German printers, in France 30, in Spain 26. Many of the earliest printers outside of Germany had learned their art in Mainz Gutenberg’s Home and where they were know as “goldsmiths”. Among those who were undeniably pupils of Gutenberg, and who probably were also assistants in the Guttenberg printing