Geometric Control and Numerical Aspects of Nonholonomic Systems Preface 1. Introduction 2. Basic geometric tools 3. Nonholonomic systems 4. Symmetries of nonholonomic systems 5. Chaplygin systems 6. A class of hybrid nonholonomic systems 7. Nonholonomic integrators 8. Control of mechanical systems References Index. Nonholonomic systems are a widespread topic in several scientific and commercial domains including robotics locomotion and space exploration. This work sheds new light on this interdisciplinary character through the investigation of a variety of aspects coming from several disciplines. The main aim is to illustrate the idea that a better understanding of the geometric structures of mechanical systems unveils new and unknown aspects to them and helps both analysis and design to solve standing problems and identify new challenges. In this way separate areas of research such as Classical Mechanics Differential Geometry Numerical Analysis or Control Theory are brought together in this study of nonholonomic systems.