The Brahmanas (; Sanskrit: , Brāhmaṇa) are a collection of ancient Indian texts with commentaries on the four Vedas. They are primarily a digest incorporating historical, records, legends, the explanation of Vedic rituals and in some cases philosophy. They are attached to each Veda, and form a part of the Hindu śruti literature. The Brahmanas are particularly noted for their instructions on the proper performance of rituals, as well as explain the symbolic importance of sacred words and ritual actions in the main text. Brahmanas lack a homogeneous structure across the different Vedas, with some containing chapters that constitute Aranyakas or Upanishads in their own right. Each Vedic shakha (school) has its own Brahmana. Numerous Brahmana texts existed in ancient India, many of which have been lost. A total of 19 Brahmanas are extant at least in their entirety. The dating of the final codification of the Brahmanas and associated Vedic texts is controversial, which occurred after centuries of verbal transmission. The oldest is dated to about 900 BC, while the youngest Brahmanas (such as the Shatapatha Brahmana), were complete by about 700 BC. According to Jan Gonda, the final codification of the four Vedas, Brahmanas, Aranyakas and early Upanishads took place in pre-Buddhist times (ca. 600 BCE).