Thirty years ago, Paul G. Hewitt developed a conceptual approach to learning physics and wrote his first book, Conceptual Physics, now in it's ninth edition. Paul's approach engages students with analogies and imagery from real-world situations to build a strong conceptual understanding of physical principles ranging from classical mechanics to modern physics. With this strong conceptual foundation, students are better equipped to understand the equations and formulas of physics, and to make connections between the concepts of physics and their everyday world. As Paul writes in his book: