What's the difference between diabetes mellitus and diabetes?

Hello, guys. I have recently heard about diabetes mellitus. I must admit that this was my first time to hear such an expression. I would like to know what the difference is between diabetes mellitus and diabetes. What do you think? Thanks to all who reply to my post. Bye, folks!

Hello. Usually, when people talk about diabetes, they think about diabetes mellitus. It is the disease related to insufficient production of insulin. This is type 1. Type 2 has a normal level of insulin, but it can’t act on target cells. Beside diabetes mellitus there is diabetes insipidus. This diabetes is related to lack of vasopressin- a hormone that is synthesized in hypothalamus and is secreted by posterior pituitary gland. It keeps water in the organism. When there is diabetes insipidus, then there is an excessive urination (polyuria). So, I guess you can say that diabetes is a wider term than diabetes mellitus.