to clarify, there are two types:
type I is the case where the individual is either born with, or receives it at an early age. Is irreversible and the person most commonly has to live with it the rest of their lives. The pancreas either doesn't work entirely, or produces so little insulin that its insufficient to support the body.
type II is when they're just fatasses and the pancreas still works, but the insulin can't reach all of the bodies cells through the bloodstream. hence the need for extra dosages of insulin.
Both most commonly associated with having multiple shots a day and not being able to eat surplus amounts of sugar
"So.. what exactly IS diabetes then?"
"uhhh.. you want the long explanation or the really fucking long explanation?"