Sutras are divided into six categories, known as the Vedangas or limbs of the Vedas. They are the Shiksha, which describes phonetics; the Chandanas, which details meter and poetic rhythm; the Vyakarana, which deals with grammar; the Nirukta, which discusses etymology; the Kalpa, which explains religious practices; and the Jyotishi, which explains astronomy.
The first four works contribute to the correct recitation and understanding of the sacred texts. The last two deal with religious rites and duties and the appropriate seasons for their performance.

Vedic texts from the fifth and fourth centuries BC dealing with phonetics and ritual injunctions and linguistics and grammar

Vedic texts from the fifth and fourth centuries BC dealing with phonetics and ritual injunctions and linguistics and grammar