Pierre de Fermat was a French lawyer at the Parlement of Toulouse, France, and an amateur mathematician who is given credit for early developments that led to infinitesimal calculus, including his adequality. In particular, he is recognized for his discovery of an original method of finding the greatest and the smallest ordinates of curved lines, which is analogous to that of the then unknown differential calculus, and his research into number theory. He made notable contributions to analytic geometry, probability, and optics. He is best known for Fermat's Last Theorem, which he described in a note at the margin of a copy of Diophantus' Arithmetica.
Born --August 17, 1601Beaumont-de-Lomagne, France
Died --January 12, 1665 (aged 63)
Fields--- Mathematics and Law
Known for ---Number theory
Fermat's Last Theorem
Influences -----François Viète