Definition: the illustrious ancient grammarian of India who is wellknown by his magnum opus, the Astaka or Astaadhyaayi which has maintained its position as a unique work on Sanskrit grammar unparalleled upto the present day by any other work on grammar, not only of the Sanskrit language, but ofany other language, classical as well as spoken. His mighty intelligence grasped, studied and digested not only the niceties of accentuation and formation of Vedic words, scattered in the vast Vedic Literature of his time, but those of classical words in the classical literature and the spoken Sanskrit language of his time in all its different aspects and shades, noticeable in the various provinces and districts of the vast country. The result of his careful study of the Vedic Literature and close observation of.the classical Sanskrit, which was a spoken language in his days, was the production of the wonderful and monumental work, the Astaadhyaayi,which gives an authoritative description of the Sanskrit language, to have a complete exposition of which,several life times have to be spent,in spite of several commentaries upon it, written from time to time by several distinguished scholars. The work is a linguist's and not a language teacher's. Some Western scholars have described it as a wonderful specimen of human intelligence,or as a notable manifestation of human intelligence. Very little is known unfortunately about his native place,parentage or personal history. The account given about these in the Kathaasaritsaagara and other books is only legendary and hence, it has very little historical value. The internal evidence, supplied by his work shows that he lived in the sixth or the seventh century B. C., if not earlier, in the north western province of India of those days. Jinendrabuddhi, the author of the Kaasikavivaranapanjikaa or Nyasa, has stated that the word शलातुर् mentioned by him in his sUtra (IV. 3.94) refers to his native place and the word शालातुरीय derived by him from the word शलातुर by that sUtra was, in fact his own name, based upon the name of the town which formed his native place. Paanini has shown in his work his close knowledge of, and familiarity with, the names of towns, villages, districts, rivers and mountains in and near Vaahika, the north-western Punjab of the present day, and it is very likely that he was educated at the ancient University of Taksasilaa. Apart from the authors of the Pratisaakhya works, which in a way could be styled as grammar works, there were scholars of grammar as such, who preceded him and out of whom he has mentioned ten viz., Apisali, Saakataayana, Gaargya, Saakalya, Kaasyapa, Bharadwaja, Gaalava, Caakravarmana Senaka and Sphotaayana. The grammarian Indra has not been mentioned by Paanini, although tradition says that he was the first grammarian of the Sanskrit language. It is very likely that Paanini had no grammar work of Indra before him, but at the same time it can be said that the works of some grammarians, mentioned by Panini such as Saakaatyana, Apisali, Gaargya and others had been based on the work of Indra. The mention of several ganas as also the exhaustive enumeration of all the two thousand and two hundred roots in the Dhaatupaatha can very well testify to the existence of systematic grammatical works before Paarnini of which he has made a thorough study and a careful use in the composition of his Ganapaatha and Dhaatupatha. His exhaustive grammar of a rich language like Sanskrit has not only remained superb in spite of several other grammars of the language written subsequently, but its careful study is felt as a supreme necessity by scholars of philology and linguistics of the present day for doing any real work in the vast field of linguistic research. For details see pp.151154 Vol. VII of Paatanjala Mahaabhsya, D. E. Society's Edition.