This book provides a comprehensive introduction to the principles and applications of quantum computing, presenting the theoretical foundations and practical developments that are shaping the next generation of computational technologies. It introduces the quantum model of computation through clear explanations of the mathematical foundations of quantum mechanics and linear algebra, followed by the study of quantum circuits and the fundamental postulates that govern quantum systems. Key concepts such as quantum entanglement, Bell's theorem, and the no-cloning principle are explored to build a deeper understanding of quantum information.

The book covers major quantum algorithms including Deutsch-Jozsa, Grover's search algorithm, Shor's factoring algorithm, and quantum phase estimation, along with modern topics such as quantum simulation and the Variational Quantum Eigensolver. It also discusses quantum complexity theory, quantum error correction, and the challenges of building reliable quantum systems. Special attention is given to the current era of noisy intermediate-scale quantum (NISQ) devices, hybrid quantum-classical algorithms, error mitigation techniques, and emerging real-world applications supported by modern quantum hardware platforms.