Signals and Systems, Second Edition, by Simon Haykin and Barry Van Veen, is designed for one- or two-semester undergraduate courses. It introduces core concepts of signals and systems, including classification, operations, and system analysis using Fourier, Laplace, and z-transforms. The book emphasizes practical applications in communications, filter design, and control systems, with a balanced approach to continuous- and discrete-time topics. This International Adaptation offers expanded content with additional examples and exercises, and features a reorganized structure in selected chapters to better support diverse learning needs and improve course alignment.