What is type 1 diabetes?

Autoimmune Dz: Type 1 diabetes mellitus (dm 1) is disease in which the beta cell of the pancreas, which produce insulin, have been destroyed by, usually in childhood. It is thought to be a result of the immune response of the body rather than the virus itself that does it. After onset, the patient no longer makes enough Insulin and will require Insulin for life.

Typically autoimmune: Usually autoimmune (anti bodies attack the Insulin making cells in the pancreas).The cells that create Insulin are destroyed and the body is dependant on exogenous Insulin (put into the body). This is much less common than type 2 diabetes which is from Insulin resistance (you need more Insulin to handle the same rise in blood sugar).