Essentials of Immunology by S.K. Gupta is a concise, well-structured textbook that serves as an accessible introduction to immunology for undergraduate and early graduate students. Its strengths include clear organization, focused coverage of core concepts, and practical emphasis on mechanisms and clinical relevance — making it especially useful for medical, dental, and allied-health learners who need a solid, exam-ready foundation without unnecessary depth.

: Coverage of antibodies, antigens, the major histocompatibility complex (MHC), and the complement system.

The immune system overreacting to harmless antigens. Standard textbooks categorize these into four types (Type I: Immediate/Allergic, Type II: Cytotoxic, Type III: Immune Complex-mediated, and Type IV: Delayed-type).