Katyayana likens speech to the supreme Brahman. He uses the Rigvedic verse – Four are its horns, three its feet, two its heads, and seven its hands, roars loudly the threefold-bound bull, the great god enters mortals (Rig-Veda, iv. 58, 3), to assert this claim. Katyayana explains that in the verse, the four horns are the four kinds of words i.e. nouns, verbs, prepositions, and particles; its three feet mean the three tenses, past, present and future; the two heads imply the eternal and temporary words, distinguished as the manifested and the manifester; its seven hands are the seven case affixes; threefold bound is enclosed in the three organs the chest, the throat, and the head; the metaphor bull (vrishabha) is used to imply that it gives fruit when used with knowledge; loudly roars signifies uttering sound, speech or language; and in the great god enters mortals entails that the great god speech, enters the mortals.[9] Thus, primal sound is often referred to as Shabda Brahman or word as The Absolute.
VEDAS
Nature
types
rigveda
yajurveda
atharvaveda
samaveda
Each veda has
the Samhitas (mantras and benedictions)
the Brahmanas (commentaries on and explanation of rituals, ceremonies and sacrifices - Yajñas)
the Aranyakas (text on rituals, ceremonies, sacrifices and symbolic-sacrifices),
the Upanishads (texts discussing meditation, philosophy and spiritual knowledge)
the Upāsanās (worship)
vedanga
Shiksha (Sanskrit: शिक्षा śikṣā, instruction, teaching): phonetics, phonology, pronunciation.
This auxiliary discipline has focused on the letters of the Sanskrit
alphabet, accent, quantity, stress, melody and rules of euphonic combination of words during a Vedic recitation
Chandas (Sanskrit: छन्दस् chandas, metre): prosody.
Vyakarana (Sanskrit: व्याकरण vyākaraṇa, grammar): grammar and linguistic analysis.
Nirukta (Sanskrit: निरुक्त nirukta, etymology): etymology, explanation of words, particularly those that are archaic and have ancient uses with unclear meaning.
Kalpa (Sanskrit: कल्प kalpa, proper. fit): ritual instructions
Jyotisha (Sanskrit: ज्योतिष
jyotiṣa, astrology): Right
time for rituals with the
help of position of nakshatras and asterisms and astronomy.