This book contains detailed descriptions and associated discussions regarding different generation, detection and signal processing techniques for the electrical and optical signals within the THz frequency spectrum (0.3–10 THz). It includes detailed reviews of some recently developed electronic and photonic devices for generating and detecting THz waves, potential materials for implementing THz passive circuits, some newly developed systems and methods associated with THz wireless communication, THz antennas and some cutting-edge techniques associated with the THz signal and image processing. The book especially focuses on the recent advancements and several research issues related to THz sources, detectors and THz signal and image processing techniques; it also discusses theoretical, experimental, established and validated empirical works on these topics. The book caters to a very wide range of readers from basic science to technological experts as well as students.