Why was the invention of the printing press a revolutionary one?

Around six hundred years ago, books were handwritten. Johannes Gutenberg was the man who saved people the trouble of writing books by had, by inventing the printing press. Gutenberg started his invention by making metal letters. He arranged them into a sentence, and pressed pieces of paper against the letters that had ink on them, with his hands. However, the ink did not come out evenly on to the paper, so he decided to make a press.

Gutenberg took some existing technologies and some of his own inventions to come up with the printing press in the year 1450. One key idea he came up with was moveable type. Rather than use wooden blocks to press ink onto paper, Gutenberg used moveable metal pieces to quickly create pages. He made innovations all the way through the printing process enabling pages to be printed much more rapidly.

The invention of the printing press spread quickly throughout Europe, and soon thousands of books were being printed on printing presses. The printing press made books cheaper and more plentiful. It made it possible for even middle class people to buy books, and spread knowledge and education like never before.