The grammar of the Sanskrit language has a complex verbal system, rich nominal declension, and extensive use of compound nouns. It was studied and codified by Sanskrit grammarians from the later Vedic period (roughly 8th century BCE), culminating in the Pāṇinian grammar of the 4th century BCE.
Vyākaraṇa
Sanskrit grammatical tradition (vyākaraṇa, one of the six Vedanga disciplines) began in late Vedic India and culminated in the Aṣṭādhyāyī of Pāṇini.
The oldest attested form of the Proto-Indo-Aryan language as it had evolved in the Indian subcontinent after its introduction with the arrival of the Indo-Aryans is called Vedic. By 1000 BCE, the end of the early Vedic period, a large body of Vedic hymns had been consolidated into the Ṛg·Veda, which formed the canonical basis of the Vedic religion, and was transmitted from generation to generation entirely orally.
In the course of the following centuries, as the popular speech evolved, there was rising concern among the guardians of the Vedic religion that the hymns be passed on without 'corruption', which for them was vital to ensure the religious efficacy of the hymns. This led to the rise of a vigorous, sophisticated grammatical tradition involving the study of linguistic analysis, in particular phonetics alongside grammar, the high point of which was Pāṇini's stated work, which eclipsed all others before him.
Pāṇini's Aṣṭādhyāyī, a prescriptive and generative grammar with algebraic rules governing every single aspect of the language, in an era when oral composition and transmission was the norm, is staunchly embedded in that oral tradition. In order to ensure wide dissemination, Pāṇini is said to have preferred brevity over clarity – it can be recited end-to-end in two hours. This has led to the emergence of a great number of commentaries of his work over the centuries, which for the most part adhere to the foundations laid by Pāṇini's work.
About a century after Pāṇini, Kātyāyana composed vārtikas (explanations) on the Pāṇinian sũtras.