Leonid Khinchin was a prominent Russian mathematician born on December 4, 1917, in Moscow. He is best known for his contributions to the fields of probability theory and mathematical statistics. Khinchin's work laid the foundation for various statistical methods and concepts that are widely used today. Throughout his career, Khinchin published numerous papers and books, significantly influencing the development of modern mathematics. He was also involved in teaching and mentoring many students, helping to shape the next generation of mathematicians. Khinchin passed away on July 31, 2004, leaving a lasting legacy in the mathematical community.