A practical introduction to numerical methods at an elementary level. It exposes students to a range of possibilities to scientific computing. Although oriented towards Mathematica, the book can be used with other programming languages. It contains lessons on Mathematica but also assumes reasonable access to the Mathematica manual. Avoiding partial derivatives which many students study but fail to master, it covers systems of ordinary differential equations to give the student an accurate picture of scientific computing. The main purpose of the book is to teach the principles of numerical analysis. In addition, it sets out to teach some simple and useful numerical methods; to indicate the sort of techniques that are used in actual numerical software and thereby suggest what kind of performance migh be expected; to give practical advice on the assessment and enhancement of accuracy; and to show how problems requiring numerical computation arise in application. Also available is an instructor's manual (0-07-057821-4).