"A Textbook of Biodiversity" by Anupam Rajak offers a comprehensive exploration of the rich and diverse world of living organisms. The first chapter introduces foundational concepts including the definition of life, biodiversity, taxonomy, systematics, and species, while also detailing the types of biodiversity, the three domains of life, taxonomical hierarchy, binomial nomenclature, and the critical roles of botanical gardens and herbaria. The second chapter delves into biodiversity patterns, its importance, and the pressing issue of biodiversity loss, further addressing conservation efforts, hotspots, endangered species, the Red Data Book, biosphere reserves, national parks, sanctuaries, and Ramsar sites. This book serves as an essential resource for understanding and preserving the planet's biological diversity.