Chen's system-first organization in Signals and Systems introduces sophomores and juniors to the fundamentals of signals and systems. The text is appropriate for courses in systems and signals for electrical, mechanical, and systems engineering, and engineering science. Chen introduces the following five major topics: fundamental concepts (causality, linearity, time-variance, and lumpedness); system analysis (the Laplace transform and the z-transform), signal analysis (the Fourier transform and frequency spectrum); stabilities and their implications (filtering, frequency response, model reduction, and op-amp circuits); and state-variable equations and computer simulations. The text provides a common background for subsequent courses in control, communication, electronic circuits, filter design, and digital signal processing.