While others before him had observed the phenomenon of gravity, Newton was the first to develop a comprehensive mathematical description of it. He formulated the Law of Universal Gravitation in his groundbreaking work, Philosophiæ Naturalis Principia Mathematica, published in 1687.

This law states that every particle of matter in the universe attracts every other particle with a force that is proportional to the product of their masses and inversely proportional to the square of the distance between them.

It's important to note that Newton's work was based on the observations and work of earlier scientists, including Galileo Galilei and Johannes Kepler.