In ancient India, the Vedas (lit. 'knowledge') are a large body of religious texts composed in Vedic Sanskrit. The texts constitute the oldest layer of Sanskrit literature and the oldest scriptures of Hinduism. There are four Vedas, which were all written during the Vedic period (Iron Age India). The oldest of these, the Rigveda, was written circa 1500–1200 BCE, while the other three Vedas (Yajurveda, Samaveda, and Atharvaveda) were written circa  1200–900 BCE. 

The four Vedas: the Rigveda, the Yajurveda, the Samaveda, and the Atharvaveda each have four subdivisions – the Samhitas (mantras, and benedictions), the Brahmanas (commentaries on and explanations of rituals, ceremonies and sacrifices aka Yajñas), the Aranyakas (text on rituals, ceremonies, sacrifices, and symbolic-sacrifices), and the Upanishads (texts discussing meditation, philosophy, and spiritual knowledge). Some scholars add a fifth category – the Upāsanās (worship). 

Vedas are śruti ("what is heard"), distinguishing them from other religious texts, which are called smr̥ti ("what is remembered"). Hindus consider the Vedas to be apauruṣeya, which means "not of a man, superhuman" and "impersonal, authorless," revelations of sacred sounds and texts heard by ancient sages after intense meditation.

Over 20,000 mantras are in the four Vedas combined. In some contexts, Veda refers only to the Samhitas, the collection of mantras, which encompass the oldest layer of Vedic texts.

The Vedas have been orally transmitted since the 2nd millennium BCE with elaborate mnemonic techniques. The mantras, the oldest part of the Vedas, are recited in the modern age for their phonology rather than semantics. They are considered "primordial rhythms of creation," preceding the forms they refer to. By reciting them, the cosmos is regenerated "by enlivening and nourishing the forms of creation at their base."