The Principia (Philosophiæ Naturalis Principia Mathematica)

*The Principia*, authored by Isaac Newton in 1687, is a groundbreaking work that formulates the fundamental laws of motion and universal gravitation. It explains how objects move on Earth and in space, showing that the same force governing falling apples also keeps planets orbiting the sun. Newton's laws describe inertia, acceleration, and action-reaction, providing a mathematical framework to predict natural phenomena. This work laid the foundation for classical mechanics, transforming our understanding of the physical universe and enabling precise scientific predictions about motion and gravity.