Owing to the superparamagnetic effect (SPE), areal storage densities achievable by today''s magnetic recording technologies are limited to around 500-800 Gbits/in2. In the past few years, the industry has managed to overcome the SPE barrier for more storage capacity. Thermal-assisted atomic force microscope (AFM) based data storage is a new attractive potential solution to supersede magnetic hard disks. This book familiarizes readers to this new data storage technology. Thermal transport in the AFM based data storage system is one of the key factors affecting this technology to successfully transfer to commercial products. Thus the emphasis of this book is placed on the issue of thermal transport in the system using atomic/molecular scale simulations. To cater the need of readers from multidisciplinary background, a large number of references have also been included in this book, which have more detailed discussion of this active research field. We hope this book would provide useful information to all those interested in the new data storage technology, and contribute to parts of its further development.