The Diamond Sūtra (Sanskrit:Vajracchedikā Prajñāpāramitā Sūtra) is a Mahāyāna (Buddhist) sūtra from the Prajñāpāramitā, or "Perfection of Wisdom" genre, and emphasizes the practice of non-abiding and non-attachment. The Diamond sutra is one of the most influential Mahayana sutras in East Asia, and is a key object of devotion and study in Zen Buddhism.

A copy of the Chinese version of Diamond Sūtra, found among the Dunhuang manuscripts in the early 20th century by Aurel Stein, was dated back to May 11, 868. It is, in the words of the British Library, "the earliest complete survival of a dated printed book."

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