Diabetes mellitus is a metabolic disorder characterized by persistently high blood glucose levels. Insulin, a hormone produced by the pancreas, helps glucose move from the bloodstream into cells to provide energy. When insulin production or insulin action is impaired, blood sugar levels can increase. The main types of diabetes include: Type 1 Diabetes: An autoimmune condition in which the body destroys insulin-producing pancreatic cells. Type 2 Diabetes: The most common type, generally associated with insulin resistance and progressive reduction in insulin production. Gestational Diabetes: Diabetes that develops during pregnancy and requires appropriate monitoring and management.