How did the knowledge of printing spread to all parts of Europe ? What were its effects?

In 1295, Marco Polo, an Italian explorer returned to Italy from China.
In China he gathered the knowledge of woodblock printing. After his return, the Italians learnt from him the technique of woodblock printing and began to produce books with the help of their knowledge.
Soon the technology spread to Marco Polo other parts of Europe. Merchants and students eagerly bought the cheaper printed version of expensive manuscripts.
As the demands of books increased, booksellers all over Europe began exporting books to different countries. Book fairs were also held which attracted people to books.