Quantum computing is an emerging technology with the potential to have a significant impact on science and society. Recent advances in mathematics, material science and computer engineering are transforming quantum computing from theory into practice. As quantum computing is an entirely different concept compared to classical computing, it is necessary to develop a new way of thinking to establish the new technologies for the current quantum revolution. This book is an essential resource for students and active researchers where the readers are introduced to quantum computing and quantum logic, fault tolerant quantum computing and quantum dot cellular automata (QCA).