Sir Isaac Newton was an English physicist, mathematician, astronomer, natural philosopher, alchemist, and theologian who is widely recognized as one of the most influential scientists of all time. He is best known for his laws of motion and universal gravitation, which form the foundation of classical mechanics. His work also laid the foundations of optics, and he made seminal contributions to the study of calculus. Newton's most famous contribution to science was his formulation of the law of universal gravitation, which states that every particle in the universe attracts every other particle with a force that is directly proportional to the product of their masses and inversely proportional to the square of the distance between them.