This book is a slow-paced introduction to quantum mechanics for undergraduates and interested laypersons. The presentation is both reader-friendly and complete. The first four chapters cover the conceptual and philosophical aspects of quantum mechanics, before the next eleven chapters gently present the mathematics underlying the subject. After an easy chapter on the history of the theory, the whole of quantum mechanics is then presented in one chapter. This is followed by applications of the theory and a revision chapter, before we go beyond undergraduate level to briefly look ahead at relativistic quantum theory.