Pāṇini's grammar defines Classical Sanskrit, so Pāṇini by definition lived at the end of the Vedic period. He notes a few special rules, marked chand… - Panini

His teacher was Varsa, and he was a contemporary of Katyayana, Vyadi, and Indradatta. Panini is said to have secured the favour of Shiva and obtained from him the alphabet in the form of fourteen pratyadhara sutras.

In the fifteenth century Rāmachandra, in his Prakriyā-kaumudī, or "Moonlight of Method," endeavoured to make Pāṇini's grammar easier by a more practical arrangement of its matter. Bhaṭṭoji's Siddhānta-kaumudī (seventeenth century) has a similar aim; an abridgment of this work, the Laghu-kaumudī, by Varadarāja is commonly used as an introduction to the native system of grammar. Among non-Pāṇinean grammarians may be mentioned Chandra (about 600 A.D.), the pseudo-Çākaṭāyana (later than the Kāçikā), and, the most important, Hemachandra (12th century), author of a Prākrit grammar.

The grammar of Panini stands supreme among the grammars of the world, alike for its precision of statement, and for its thorough analysis of the roots of the language and of the formative principles of words. By employing an algebraic terminology, it attains a sharp succinctness unrivalled in brevity, but at times enigmatical. It arranges, in logical harmony, the whole phenomena which the Sanskrit language presents, and stands forth as one of the most splendid achievements of human invention and industry. So elaborate is the structure, that doubts have arisen whether its complex rules of formation and phonetic change, its polysyllabic derivatives, its ten conjugations with their multiform aorists and long array of tenses, could ever have been the spoken language of a people.