Pafnuty Chebyshev was born on May 16, 1821 in Okatovo, Russia. He taught mathematics at the University of St Petersburg.
Chebyshev mathematical contributions include number theory, geometry, quadratic forms, and the theory of integrals. To students of probability and statistics, Chebyshev is best known for the inequality that gives an upper bound on the probability of a large deviation from the mean.
Chebyshev was elected a Fellow of the Royal Society in 1877. He died on December 8, 1894 in Petersburg.