Signals are physical manifestations of underlying processes or phenomena. The evolution of a physical process is captured in the form of a signal, which is mathematically represented as a function of an independent variable. For example, the temperature inside a room is captured using a thermometer by making measurements at discrete time instants. Systems, on the other hand, process the signals fed to them and at the end of the process emit another signal. Like signals, even systems are also represented as a function of an independent variable. Signals can be characterized in terms of parameters like energy and power, to name a few. Applications of signals and systems can be found in diverse areas like electrical engineering (EE), mechanical engineering, and financial engineering. Specifically, in EE curriculum, signals and systems have many applications in communication and control system design and analysis. This monograph can serve as an excellent textbook for undergraduate students in electrical and mechanical engineering disciplines.

There have been numerous undergraduate-level textbooks that delve into the basic concepts of signals and systems. The book Signals and systems [1] has served as an excellent textbook on this subject over the years. Broadly, the contents of this book by Sadiku and Ali parallel that of [1], although the treatment is somewhat concise. The book starts off with a quick introduction to basic concepts on signals and systems in chapter 1, followed by a thorough understanding of convolution operation in chapter 2. Chapters 3, 4, and 5 touch upon the Laplace and Fourier transforms that are used extensively for analysis of continuous time signals and systems. Chapters 6 and 7 deal with the discrete time Fourier transform and the z-transform that are used for analysis of discrete time signals and systems. A unique aspect of this book is the use of MATLAB, which is widely used to perform scientific computing in industry and academia. Appendix C gives an overview of how to get started with MATLAB, and in the regular chapters of the book the various concepts are demonstrated by using examples created in MATLAB.

In conclusion, the monograph does a commendable job in presenting the basics of signals and systems. The theory is well complemented by the exercises created in MATLAB. Perhaps the authors will consider including exercises based on R or Python in future editions. This would help cater to a much larger audience owing to the open-source nature of both R and Python. This monograph could potentially serve as textbook for a basic course on signals and systems. I am familiar with another book by M. N. O. Sadiku, Principles of electromagnetics [2], and sincerely feel that the current monograph could also have the same effect in preparing undergraduate students for advanced courses in electrical communication systems, control systems, and signal processing.