VEDAS

The word veda means knowledge.  There are four Vedas, dating from the earliest period of known Indian scriptures.  They are the Rig Veda, a collection of praises in the form of hymns; the Sama Veda, also a collection of hymns; the Yajur Veda, a collection of sacrificial formulas; and the Atharva Veda, a collection of charms and magic formulas.  They are known together as Samhitas (Collections).

The Vedas consist of a ritual or "work" portion called Karmakanda, and a philosophical or "knowledge" portion called Jnanakanda. 

Each ritual portion is a collection of mantras or, again, hymns, most of which are addressed to deities such as Indra or Varuna.  The ritual portion known as Brahmanas is concerned with details of sacrificial rites and with specific duties and rules of conduct.  The ritual portion known as Aranyakas is forest treatises so called, which emphasize the spiritual interpretation of religious rites and ceremonies. 

Each knowledge portion comprises Upanishads, a term meaning to sit next to or under (a teacher), and also "secret teaching."

Practically all our knowledge of early Hinduism is drawn from the study of the Vedas.