This book, a translation of an original French text, is written in two parts: the first revises the ideas and theoretical bases necessary for a good understanding of the techniques used in the second, which deals with applications of MATLAB(R) and SIMULINK(R) in process control and digital signal processing. Each application is treated through various techniques including the classical methods of automation and of deterministic and random digital processing using fuzzy logic and neural networks. The preceding mathematical study of the physical processes goes from finding the equations to editing the analogical model. Beyond the utilisation of M files, the use of SIMULINK(R) and S-functions, to which an appendix is dedicated, is emphasized. The encapsulation of diagram-blocks, enabling the creation of personalised libraries, one of SIMULINK(R)'s functionalities, has been treated in the appendix. The following SIMULINK(R) toolbox functions and blocks have been used: "Control System TOOLBOX", "Signal Processing TOOLBOX", "Neural Network TOOLBOX" and "Fuzzy Logic TOOLBOX". This book is intended for technicians, engineers, academic and industrial researchers who will find here the necessary mathematical tools offered by MATLAB(R), the TOOLBOXES and SIMULINK(R), for the rapid and efficient solution of problems in modeling and in digital or analogical calculation.