Vedic literature, in particular the Puranas ('ancient'; similar to encyclopedias) and Itihasa ('chronicle, history, legend'), narrate numerous avatars of Vishnu. The most well-known of these avatars are Krishna (most notably in the Vishnu Purana, Bhagavata Purana, and Mahabharata; the latter encompassing the Bhagavad Gita), and Rama (most notably in the Ramayana). Krishna in particular is venerated in Vaishnavism as the ultimate, primeval, transcendental source of all existence, including all the other demigods and gods such as Vishnu.