The study of Calculus enables us to solve problems and articulate abstract concepts far beyond the theoretical reach of Algebra. The power of Calculus derives from the ingenuity and simplicity of its notation. This mathematical language allows the mathematician the freedom and immense versatility to accurately describe physical problems and the tools to solve them. This book consists of lectures on all the topics of a 3-course series on Calculus: Calculus I, II, and III. It can be used as a textbook, or as a supplement to other texts. Both students and instructors will find it helpful in elucidating the ideas and methods of Calculus.