Scilab is a free open-source software package for scientific computation. This is the first book to focus on simulation and modeling, and to put a major emphasis on Scicos and discuss it in depth. This new edition includes expanded chapters and major rewrites. Scilab and its Scicos block diagram graphical editor, with a special emphasis on modeling and simulation tools. The first part is a detailed Scilab tutorial, and the second is dedicated to modeling and simulation of dynamical systems in Scicos. The concepts are illustrated through numerous examples, and all code used in the book is available to the reader.