Hindu texts Vedas: the Rigveda, the Yajurveda, the Samaveda and the Atharvaveda. Each Veda has been subclassified into four major text types – the Samhitas (mantras and benedictions), the Aranyakas (text on rituals, ceremonies, sacrifices and symbolic-sacrifices), the Brahmanas (commentaries on rituals, ceremonies and sacrifices), and the Upanishads (text discussing meditation, philosophy and spiritual knowledge). The Upanishads are a collection of Hindu texts which contain some of the central philosophical concepts of Hinduism. The Upanishads are commonly referred to as "Vedānta", variously interpreted to mean either the "last chapters, parts of the Veda" or "the object, the highest purpose of the Veda".
Indra the most celebrated Vedic deities. He is also mentioned in ancient Indo-Iranian literature, but with a major inconsistency when contrasted with the Vedas. In the Vedic literature, Indra is a heroic god. In the Avestan (ancient, pre-Islamic Iranian) texts such as "Vd." 10.9, "Dk." 9.3 and "Gbd" 27.6-34.27, Indra – or accurately Andra – is a gigantic demon who opposes truth. In the Vedic texts, Indra kills the archenemy and demon Vritra who threatens mankind. In the Avestan texts, Vritra is not found. Indra is called "vrtrahan-" (literally, "slayer of Vritra demon") in the Vedas, which corresponds to Verethragna of