This book is intended to serve two purposes: one to introduce students in nuclear and radiological engineering to Python and to use Python as a pedagogical tool for numerical methods relevant to their studies. The audience for this book is intended to be junior and senior undergraduate students. Most of the material is, however, suitable for sophomore students if appropriate background is provided for the nuclear reactor and radiation physics. The book arose out of a set of lecture notes for a course at Texas A&M University that was for juniors who had previously taken a course in nuclear reactor theory.