Superb explanation of the conceptual foundations of calculus. Comenetz uses a few different examples from physics to portray the fundamental concepts behind calculus. This is much more than a book that teaches you how to solve calculus problems; it teaches you the essential concepts that unify all applications of calculus. After reading this book you will have a much deeper understanding of the subject than most textbooks provide. Comenetz is an excellent writer. His explanations are lucid, and he builds everything from the ground up. Anyone with a background in pre-calculus material (algebra, trignometry, logarithms, basic geometry) will have no problem following his narrative. He provides numerous examples, and frequent sections of problems. And, unlike most mathematics textbooks, he provides answers to all of the problems. If you are looking for a book that will give you a thorough understanding of what calculus really is, this is the book to read.