It is one of the five elements that constitute the traditional almanacs called Pañcāṅga-s the other four being Nakshatra, Tithi, Karaṇa and Nityayoga.
[1] The concept of week, the unit of time consisting of seven days, is indigenous to Indian civilisation.
The concept was probably borrowed by Babylonians and its use predates the use of the twelve zodiacal signs in Indian civilazation.
Sūrya Siddhānta, in Chapter XII Bhūgolādhyāya Verses 78–79, says:[2] Explanation of the rationale This rationale is reflected in one of the literal meanings of the Sanskrit word vāsara (another term for vāra) which is "relating to or appearing in the morning".
It is probably the case that the ancient Indian astronomers and astrologers borrowed the concept of vāra or week from the Chaldeans.