Woodblock printing
Woodblock printing made the written word available to vastly greater audiences. One of the world's oldest surviving printed documents is a miniature Buddhist "dharani" sutra unearthed at Xi'an in 1974 and dated roughly from 650 to 670. The "Diamond Sutra" is the first full-length book printed at regular size, complete with illustrations embedded with the text and dated precisely to 868. Among the earliest documents to be printed were Buddhist texts as well as calendars, the latter essential for calculating and marking which days were auspicious and which days were not. With so many books coming into circulation for the general public, literacy rates could improve, along with the lower classes being able to obtain cheaper sources of study. Therefore, there were more lower-class people seen entering the Imperial Examinations and passing them by the later Song dynasty. Although the later Bi Sheng's movable type printing in the 11th century was innovative for his period, woodblock printing that became widespread in the Tang would remain the dominant printing type in China until the more advanced printing press from Europe became widely accepted and used in East Asia. The first use of the playing card during the Tang dynasty was an auxiliary invention of the new age of printing.