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The word Puranas (, , ;) literally means "ancient, old", and it is a vast genre of Indian literature about a wide range of topics, particularly myths, legends and other traditional lore. Composed primarily in Sanskrit, but also in regional languages, several of these texts are named after major Hindu deities such as Vishnu, Shiva and Devi. The Puranas genre of literature is found in both Hinduism and Jainism.
The Puranic literature is encyclopedic, and it includes diverse topics such as cosmogony, cosmology, genealogies of gods, goddesses, kings, heroes, sages, and demigods, folk tales, pilgrimages, temples, medicine, astronomy, grammar, mineralogy, humor, love stories, as well as theology and philosophy. The content is highly inconsistent across the Puranas, and each Purana has survived in numerous manuscripts which are themselves inconsistent. The Hindu Puranas are anonymous texts and likely the work of many authors over the centuries; in contrast, most Jaina Puranas can be dated and their authors assigned.
There are 18 Maha Puranas (Great Puranas) and 18 Upa Puranas (Minor Puranas), with over 400,000 verses. The first versions of the various Puranas were likely composed between the 3rd- and 10th-century CE. The Puranas do not enjoy the authority of a scripture in Hinduism, but are considered a Smriti.
They have been influential in the Hindu culture, inspiring major national and regional annual festivals of Hinduism. Their role and value as sectarian religious texts and historical texts has been controversial because all Puranas praise many gods and goddesses and "their sectarianism is far less clear cut" than assumed, states Ludo Rocher. The religious practices included in them are considered Vaidika (congruent with Vedic literature), because they do not preach initiation into Tantra. The Bhagavata Purana has been among the most celebrated and popular text in the Puranic genre, and is of non-dualistic tenor. The Puranic literature wove with the Bhakti movement in India, and both Dvaita and Advaita scholars have commented on the underlying Vedantic themes in the Maha Puranas.