On August 24, 1456, the Bible was printed for the first time. The groundbreaking project was started four years earlier by Johannes Gutenberg in Mainz, Germany, marking the start of the "Gutenberg Revolution" and the age of the printed book. Gutenberg's invention, the printing press, used movable components to applied ink on paper as a means towards producing text. Although not the inventor of such a device (the world's first known movable-type system was created in China around 1040 CE), Guttenberg revolutionized the process by enabling mass printing. The “hand mold” he created made possible for the first time the precise and rapid creation of “types” in large quantities, a key element in the profitability of the whole printing enterprise. Originally a goldsmith, Gutenberg used his knowledge of metals to develop an alloy of lead, tin and antimony to forge his type pieces that would imprint clearer characters. In fact, that same alloy is still used today. Up until now, practically all movable-type printing ultimately derives from Gutenberg's original machine, which is often regarded as the most important invention of the second millennium.Although the printing era was welcomed by most, the Catholic Church opposed the technological revolution. Ironically, the Bible was the source of the controversy; the Church feared that the spread of theological learning in the vernacular would result in a loss of power and influence. In 1515, Pope Leo X tried to introduce a censorship and a supervision of printed books. This measure had little effect.It is believed that a total of 180 copies of the "Guttenberg Bible" were produced, 135 on paper and 45 on vellum, which is a high quality parchment. Widely praised for its high aesthetic and artistic qualities, the book has an iconic status in the West. Only twenty-one complete copies survived the five centuries since their printing, and are considered the most expensive books on the planet based on auction prices.In a turn of events, the clergy that was once opposed to mass producing the Bible is now the driving force behind its continued printing around the world. In the US, the American Bible Society is the original publisher of the Good News Bible which can now be found in almost every motel. In Israel, the Military Rabbinate is responsible for ordering millions of copies which are handed to every soldier in the IDF after completing boot camp. While no longer as popular as it was during the centuries leading up to the era of the Guttenberg press, the Bible is still the most popular book in the world with close to three billion copies printed in several hundred languages; the second most popular book being the Koran and the third – Mao Zedong's little red book.