Hindu texts to an author, as a derivative work they are considered less authoritative than "Sruti" in Hinduism. The Smrti literature is a vast corpus of diverse texts, and includes but is not limited to Vedāngas, the Hindu epics, the Sutras and Shastras, the texts of Hindu philosophies, the Puranas, the Kāvya or poetical literature, the "Bhasyas", and numerous "Nibandhas" (digests) covering politics, ethics, culture, arts and society. Many ancient and medieval Hindu texts were composed in Sanskrit, many others in regional Indian languages. In modern times, most ancient texts have been translated into other Indian languages and some in Western languages.
Ancient Iranian religion sources on Iranian myths, both from indigenous texts and classical authors, originated after the emergence of Zoroastrianism, it is difficult to distinguish between myths that are Zoroastrian innovations from that those that are inherited. The fact that Zoroastrianism is heavily inspired by already existing ideas and has adapted from previous Iranian religions makes this discerning particularly hard. Like other ancient religions in general, Iranian religions did not have main collection of myth. Iranian myths are rather fragments from a diverse variety of myths that exhibit variations in common themes. There is a variant of the Noah's Ark myth in Iranian