The principle behind printing is not very complicated, but immense amounts of complexity are invested in the mass production of printed documents. Invented by Johannes Gutenberg in the mid-15th century, the early printing presses used a flat tray of inked type. Once paper was placed over the type, a surface was applied and the ink was pressed into the paper. While an improvement over the traditional duplication methods of the time (being meticulous hand-scribing of volumes), it was a slow and tedious process to use. Around 1800 the first cylinder press was created, followed by the large and immensely fast rotary presses. Today, computers have taken this ancient art out of the craftsman's workshop and placed it on the desktop. Desktop publishing revolutionized the creation of printed documents, not only from the standpoint of speed and accuracy, but also by enabling anyone to mass-produce the printed word without investing the many years it takes to learn the trade.