This book provides a comprehensive introduction to quantum mechanics, supported by numerous solved exercises. Aiming to be both exhaustive and educational, it minimises overly formal aspects by presenting the wave mechanical approach to quantum mechanics. The book simplifies and rigorously covers a large set of fundamental topics such as potential wells and barriers, wave packets, harmonic oscillators, and the hydrogen atom. It also addresses spin and, in simple terms, the conceptual difficulties of quantum physics and Bell’s inequalities. The discussion extends to relativistic quantum mechanics. Each chapter includes exercises designed to test comprehension and facilitate optimal assimilation of the material, and are followed by detailed solutions. Intended for both personal study and course support, this book is valuable for anyone curious about the subject. However, it is specifically targeted at undergraduate and master’s students in physics, chemistry, and mathematics, as well as engineering students.