Isaac Newton was a pioneering physicist and mathematician born in 1642 in England. He is best known for his laws of motion and universal gravitation, which laid the groundwork for classical mechanics. Newton also made significant contributions to optics and developed calculus independently alongside Gottfried Wilhelm Leibniz. His influential work, "Philosophiæ Naturalis Principia Mathematica," published in 1687, articulated his theories on motion and gravity.