This textbook on signals and systems provides a complete array of MATLAB tools specifically designed for the course, compatible with MATLAB 3.5 or 4.0. This software tool is used in the context of a presentation of systems concepts and analysis techniques. Use of MATLAB helps students to understand what the mathematical abstractions represent, which helps them to understand the behavior of a variety of systems. In response to a wide range of signal inputs.The software provides students with instantaneous feedback which encourages them to explore problems further. Topics covered in the text include signals, systems, convolution, Fourier series and transforms, Laplace transforms, analog filters, sampling, the discrete-time Fourier transform (DTFT), FFT, z-transforms and digital filters. All basic concepts are illustrated by worked examples. End-of-chapter problems include simple drills as well as more challenging exercises that develop or extend the concepts covered. A unique (but optional) feature of this text is the software supplied on disk which contains ready-to-run demonstrations, interactive programs and full-fledged general purpose programs. ..The software runs under MATLAB and includes routines developed for plotting functions, generating random signals, regular and periodic convolution, analytical and numerical solution of differential and difference equations, Fourier analysis, frequency response, asymptotic Bode plots, closed form expressions for Laplace and z-transforms and inverse transforms, classical analog filter design, sampling, quantization, interpolation, FIR and IIR filter design using various methods, and more. So as not to affect the continuity and logical flow of the text material, the programs are described and used only in the accompanying documentation on disk. A MATLAB appendix to each chapter lists the appropriate programs, and each section that can be tied to the software is marked.