Symmetric Boolean functions have played an important role in many aspects of design automation for many years. This book summarizes developments and provides a collection of new tools and techniques that can be used to advance the study of Boolean functions. Moreover, Boolean functions provide the necessary framework for expressing the operation of logic gates, which are the key building units for the accomplishment of signal processing tasks in fundamental and system-oriented levels. The book concludes with a discussion on how Boolean functions can be used to ensure the minimum degree of logical functionality between light-wave modulated signals.