Organic Chemistry: Principles from Molecules to Macromolecules is a comprehensive textbook for students and professionals looking to get a solid knowledge of organic chemistry’s fundamental principles and applications. From tiny, basic molecules to intricate macromolecules, the book focusses on the fundamentals that underlie the structure, behaviour, and reactivity of organic molecules. The book starts by teaching essential concepts like hybridisation, molecular geometry, and functional groups, providing a strong foundation for readers. In order to comprehend how molecular structure affects chemical characteristics and biological activity, it explores stereochemistry, specifically isomerism, chirality, and optical activity. The book advances by covering essential reaction processes such as addition, substitution, and elimination. Through the analysis of reaction kinetics and energy diagrams, readers will acquire knowledge about the function of catalysts and reaction pathways. Real-world applications enhance the talks and emphasise the significance of organic molecules in material science, agriculture, and medicines. The sections on macromolecules (proteins, carbohydrates, and nucleic acids) demonstrate the complex link between structure and function in biological systems. The importance of polymers—both natural and synthetic—and their uses in daily life are also emphasised in the book. Throughout the book, there are various images, examples, and problem sets to help readers understand and retain complicated topics. Organic Chemistry: Principles from Molecules to Macromolecules gives readers the skills they need to approach organic chemistry confidently by bridging the gap between theoretical knowledge and real world applications. This helps readers develop a greater understanding of the subject’s significance in science and industry. Anyone working in the subject of organic chemistry will benefit greatly from this book, whether they are using it for professional reference or academic study.