The proposal is to present in a book the most advanced techniques employed to model and simulate metallic nanoparticles, and to make these methods appealing and understandable to people performing experiments. Nanotechnology is an area undergoing dramatic and intense changes, being also multidisciplinary, where several research fields (physics, chemistry, biology) converge. However, in many cases the connection between experimental and theoretical research is not the most favorable and this is in part due to the "great gap" that exists between both. The main reason for this is the wide range of terms involved in the different disciplines and of course, the occurrence of specialists coming from diverse areas. In the light of this perspective, the motivation to edit the present book is not only to give a summary of the state of the art in the theoretical field, but also to explain why and how these tools could be helpful to experimentalists. The final purpose of this book is to smooth over these difficulties.
A further motivation to consider nanoparticles is that their production and the study of their properties is probably the most evident outcome of nanoscience and nanotechnology.