This document discusses the epidemiology of diabetes mellitus. It begins with defining diabetes and classifying its various types. Globally, the prevalence of diabetes has been increasing rapidly and is projected to continue rising significantly. In India specifically, diabetes prevalence is around 8.6% currently with over 50% of cases being undiagnosed. Key risk factors include obesity, physical inactivity, and diet. Prevention efforts focus on promoting healthy lifestyles while management involves screening, treatment, and self-care education to control blood sugar and prevent complications.