Panini was a Sanskrit grammarian who was born in about 520 BC in India and died at about 460 BC.  In Panini's treatise called Astadhyayi, he distinguishes the language of sacred texts and the usual language of communication as well as formulating formal production rules and definitions to describe the Sanskrit grammar.  John Backus independently invented Backus Naur Form (BNF), a standard notation to describe the syntax of a high level programming language and Panini's notation in his treatise is equivalent in its power of that of Backus and has many similar properties.  From the similarities between Panini's treatise and BNF, he is thought of by the author of the website to be the "forerunner of modern formal language theory used to specify computer languages."

Author: Sergio Gonzalez

References:
http://www-groups.dcs.st-and.ac.uk/~history//Mathematicians/Panini.html
http://www-groups.dcs.st-and.ac.uk/~history//Mathematicians/Backus.html