Philosophy of power system Protection and Security, Computer-Aided design and analysis: is a textbook that provides an excellent focus on the advanced topics of power system protection and gives exciting analysis methods and covers the important applications in the power systems relaying. Each chapter opens with a historical profile or career talk, followed by an introduction that states the chapter objectives, links the chapter to the previous ones, and then introduces each chapter. All principles are presented in a lucid, logical, step-by-step approach. The authors avoid wordiness and detail overload that could hide concepts and impede understanding as much as possible. In each chapter, the authors present some of the solved examples and applications using a computer program. Toward the end of each chapter, the authors discuss some application aspects of the chapter's concepts using a computer program. In recognition of requirements by the Accreditation Board for Engineering and Technology (ABET) on integrating computer tools, the use of MATLAB® is encouraged in a student-friendly manner. MATLAB® is introduced and applied gradually throughout the book. Practice problems immediately follow each illustrative example. Students can follow the example step by step to solve the practice problems without flipping pages or looking at the book's answers. These practice problems test students' comprehension and reinforce key concepts before moving on to the next section. The book is intended as a textbook for a senior-level undergraduate student in electrical and computer engineering departments and appropriate for Graduate Students, Industry Professionals, Researchers, and Academics. The book has more than ten categories and millions of power readers. It can use in more than 400 electrical engineering departments at the top of universities worldwide. Based on this information, targeted lists of the Engineers from which specific disciplines -Electrical, Computer, Power Control, Technical power system, Protection, Design, and Distribution engineers. Designed for a three-hour semester course on power system protection and security is intended as a textbook for a graduate,senior-level undergraduate student in electrical and computer engineering. The prerequisites for a course based on this book are knowledge of standard mathematics, including calculus and complex numbers. Based on this information, targeted lists of the Engineers from which specific disciplines will purchase -Electrical engineers -Computer engineers. -Power Control engineers. -Electronics engineers. - Technical power system engineers -Protection engineers -Design engineers. -Distribution engineers. The book gives rich information for the industrial engineer and electric control engineer because it contains more details about power network protection and security. The reader will able to modeling, designing, and implement different parts of the power system relaying after he/she finishes reading this book. The book's strengths -The book using for various academic and industrial levels. -The book is giving rich and essential information about power systems and provide the fundamental study for the next book (power system protection and control) -The book Including a lot of solved examples and problems in each chapter. -The results were obtained from the MATLAB program for different topics. -Power system protection and control will include in the next part of the book. After finish reading the book, the reader will be able to manage and control the power system parameters, and it will help him in power station work and control centers. The book will assist the researchers in their field of power system track. The student will improve coordination between power demand and generation and use of modern information technology and program.