Philosophiæ Naturalis Principia Mathematica, commonly known as the Principia, is a seminal work in the field of physics written by Isaac Newton and first published in 1687. This groundbreaking book lays the foundation for classical mechanics, introducing the laws of motion and universal gravitation that describe the behavior of objects in motion and the forces acting upon them. The Principia not only revolutionized the understanding of the physical world but also established a new framework for scientific inquiry. Its rigorous mathematical approach and profound insights have influenced countless scientists and thinkers, making it one of the most important works in the history of science.