Diabetes mellitus is a group of metabolic diseases involving carbohydrate, lipid, and protein metabolism. It is characterized by persistent hyperglycemia which results from defects in insulin secretion, or action or both. Diabetes mellitus has been known since antiquity. Descriptions have been found in the Egyptian papyri, in ancient Indian and Chinese medical literature, as well as, in the work of ancient Greek and Arab physicians. In the 2~(nd) century AD Aretaeus of Cappadocia provided the first accurate description of diabetes, coining the term diabetes, while in 17~(th) century Thomas Willis added the term mellitus to the disease, in an attempt to describe the extremely sweet taste of the urine. The important work of the 19~(th) century French physiologist Claude Bernard, on the glycogenic action of the liver, paved the way for further progress in the study of the disease. In 1889, Oskar Minkowski and Joseph von Mering performed their famous experiment of removing the pancreas from a dog and producing severe and fatal diabetes. In 1921, Frederick Banting and Charles Best extended Minkowski’s and Mering’s experiment. They isolated insulin from pancreatic islets and administrated to patients suffering from type 1 diabetes, saving thus the lives of millions and inaugurating a new era in diabetes treatment. Diabetes mellitus is a group of metabolic diseases involving carbohydrate, lipid, and protein metabolism. It is characterized by persistent hyperglycemia which results from defects in insulin secretion, or action or both. Diabetes mellitus has been known since antiquity. Egyptian papyri, in ancient Indian and Chinese medical literature, as well as, in the work of ancient Greek and Arab physicians. In the 2 ~ (nd) century AD Aretaeus of Cappadocia provided the first accurate description of diabetes, coining the term diabetes, while in 17 ~ (th) century Thomas Willis added the term mellitus to the disease, in an attempt to describe the extremely sweet taste of the urine. The important work of the 19 ~ (th) century French physiologist Claude Bernard, on the glycogenic action of the liver, paved the way for further progress in the study of the disease. In 1889, Oskar Minkowski and Joseph von Mering performed their famous experiment of removing the pancreas fro In 1921, Frederick Banting and Charles Best extended Minkowski’s and Mering’s experiment. They isolated insulin from pancreatic islets and administered to patients suffering from type 1 diabetes, saving thus lives in millions and inaugurating a new era in diabetes treatment.