The book presents cutting-edge technologies-digitalization, decentralization, and electrification-that are transforming the control and operation of modern power systems. These innovations encompass active distribution and transmission networks, smart grids, microgrids, and the integration of diverse distributed energy resources such as solar photovoltaics, wind turbines, fuel cells, micro-turbines, energy storage systems, conventional diesel generators, and other advanced systems. This book explores these advanced technologies in depth, with a focus on their application in power distribution and transmission systems. It serves as a valuable resource for academicians, researchers, and industry professionals, offering insights into emerging technologies, innovative research directions, real-world experiences, and practical approaches to technology deployment in electrical power and energy systems.