The printing press and the information revolution

In medieval Europe a book had to be copied by hand. A single Bible could take a scribe many months, and books were expensive enough that libraries chained them to desks. Copying also introduced errors, so no two manuscripts were exactly alike.

Printing itself was not new. Woodblock printing was used in China by the seventh century, the Diamond Sutra of 868 is the oldest dated printed book, and Bi Sheng created movable type from baked clay in the eleventh century. Korean printers used movable metal type in the thirteenth and fourteenth centuries. But for languages with thousands of characters, movable type offered less advantage than for alphabets.

Around 1440 Johannes Gutenberg, a goldsmith in Mainz, developed a complete printing system. Its key was a hand mould that could cast large numbers of identical metal letters quickly from an alloy of lead, tin and antimony. He combined this with an oil-based ink that stuck to metal and a screw press adapted from those used for wine and paper.

The Gutenberg Bible, printed around 1455, showed what the system could do. Roughly 180 copies were produced, and about 49 survive in whole or in large part.

Printers carried the technology across Europe with astonishing speed. By 1500, presses were operating in more than 250 towns, and they had produced millions of books. Venice became a major centre, where Aldus Manutius published affordable, portable editions of classical texts.

The price of books fell sharply, and printed pamphlets and broadsheets made short texts cheaper still. In England, William Caxton set up a press in 1476 and printed works in English, which helped standardise spelling and grammar.

When Martin Luther published his criticisms of the church in 1517, printers quickly reproduced them. Luther wrote in accessible German, and his pamphlets sold in enormous numbers. Within a few years his ideas had spread across German-speaking lands faster than church authorities could respond.

His translation of the Bible into German allowed ordinary readers to study scripture directly. Print did not cause the Reformation by itself, but it made a local dispute into a continent-wide movement that could not be contained.

• Scientists could publish identical copies of diagrams, tables and data, so errors could be spotted and corrected across editions.
• Standard printed texts made it easier to compare and build on others' work, supporting the scientific revolution.
• Vernacular printing strengthened national languages at the expense of Latin.
• Literacy slowly spread as reading material became cheaper and more common.
• Governments and churches introduced censorship and licensing to control what could be printed.

Hand presses worked in much the same way for three and a half centuries. In the nineteenth century, steam-powered presses and cheap paper made from wood pulp allowed daily newspapers with huge circulations, and later innovations such as the Linotype machine sped up typesetting.

Historians often compare the printing press to the internet: both lowered the cost of spreading information dramatically, empowered new voices, weakened old authorities, and also spread propaganda and misinformation more easily.