Pāṇini was a Sanskrit grammarian, logician, philologist, and revered scholar in ancient India during the mid-1st millennium BCE, dated variously by most scholars between the 6th–5th and 4th century BCE.
The historical facts of his life are unknown, except only what can be inferred from his works, and legends recorded long after. His most notable work, the Aṣṭādhyāyī, is conventionally taken to mark the start of Classical Sanskrit. His work formally codified Classical Sanskrit as a refined and standardized language, making use of a technical metalanguage consisting of a syntax, morphology, and lexicon, organised according to a series of meta-rules.
Since the exposure of European scholars to his Aṣṭādhyāyī in the nineteenth century, Pāṇini has been considered the "first descriptive linguist", and even labelled as "the father of linguistics". His approach to grammar influenced such foundational linguists as Ferdinand de Saussure and Leonard Bloomfield.