When Gutenberg was done printing a page using his movable-type method he would simply remove the plate and then remove all the individual letters and then be able to reuse everything. This process allowed books to be created more quickly and cheaply. Did you find the 3 changes? Click to see the next puzzle.
Because of this innovative process Gutenberg wanted to keep his printing press very secretive. If he could out-print all the other bookmakers he could make lots of money.