The accumulated highest knowledge of ancient Indian culture revealed to the Saptarishis, seven (sapta) seers (rishis). These rishis were not humans (purusha), therefore the Veda is considered apurusheya – not written by humans. What is written by human is purusheya.
The Veda is shruti, eternal knowledge revealed to the highest consciousness, ‚heard‘ by the Saptarishis. Shruti is an immutable truth … the sun rises daily. Smriti is written, ‚remembered‘ knowledge, taken from the Shruti. Mostly they are instructions … at sunrise you have to do this or that. The best-known Smriti is the Manusmriti, the ‘Law of Manu’.
The Veda was divided into 4 Vedas, 6 Vedangas, 4 Upavedas, by Vyasa, Vedavyasa in this ‚function‘.
Vyasa had five disciples: Vaishampayana, Jaimini, Paila, Sumantu and Shuka, his son.
The four Vedas
Rig Veda – Hymns of invocation – Vyasa taught this Veda to Paila.
Sama Veda – Liturgical chants from the Rig Veda – Vyasa taught this Veda to Jaimini.
Yajur Veda – Offerings – Vyasa taught this Veda to Vaishampayana.
Atharva Veda – Magic spells – Vyasa taught this Veda to Sumantu.
Three priests have the following tasks in the sacrifice
Hota / Hotri – Recites the mantras of the Rig Veda.
Adhvaryu – Observes the rites of the Yajur Veda.
Udgatri – Sings the hymns of Sama Vedas.
The six Vedangas – Additions
Jyotisha – Astrology and Astronomy
Kalpa – Rites
Shiksha – Phonetics
Chandas – Metrics
Nirukta – Etymology
Vyakarana – Grammar
The four Upavedas – subordinate Vedas, which contain practical knowledge.
Dhanur Veda – The knowledge of the art of war is integrated into the Rig Veda
Gandharva Veda – The knowledge of music and dance is integrated into the Sama Veda
Ayur Veda – The knowledge of life – is integrated into the Atharva Veda
Sthapatya Veda – The knowledge of architecture is integrated into the Yajur Veda