Humans have been trying to understand the physical universe since antiquity. Aristotle had one vision and Einstein another. More often than not, these different understandings begin with a simple drawing, a pre-mathematical picture of reality. Such drawings are a humble but effective tool of the physicist’s craft, part of the tradition of thinking, teaching, and learning passed down through the centuries. This book uses drawings to help explain fifty-one key ideas of physics accessibly and engagingly. Don Lemons, a professor of physics and author of several physics books, pairs short, elegantly written essays with simple drawings that together convey important concepts from the history of physical science.