This document provides brief biographies of famous mathematicians including Euclid, Carl Gauss, Leonhard Euler, Pythagoras, Aryabhata, and Fermat. It discusses their major contributions such as Euclid establishing the principles of geometry, Gauss' work in number theory and algebra, Euler making advances in many fields of mathematics through his notations and methods, Pythagoras discovering relationships in music and numbers, Aryabhata developing India's place value system and early work in trigonometry and algebra, and Fermat's foundational work in number theory and discoveries in analytic geometry and calculus.