The book is divided into two sections based on the sources of disease: Genetic and Congenital Diseases and Environmental Diseases Human bodys cells respond to various stimuli/injuries in only a few finite ways: Stay same (homeostasis) adjust (adaptations) suffer reversible injury suffer irreversible fatal injury and die or suffer irreversible non-fatal injury to its genetic apparatus and develop neoplasms. These phenomena are described in Section 1 in Chapters 1 to 4 as: Cell Injury Inflammation and Repair Disorders of the Immune System Neoplasm/Neoplasia. Disorders pertaining to the blood flow (haemodynamic disorders) are described in Chapter 5. Applications of these fundamental facts to the various systems of our body are described in Section 2 in Chapters 8 to 18 as HS CVS RS GIS US NS ES REP. S MSS Skin and E & E. The book aims to serve the undergraduate medical students in revising the course material and appearing in their examinations with full knowledge and confidence.