Diabetes Insipidus v/s Diabetes Mellitus

Diabetes Insipidus (Water Diabetes)	Diabetes Mellitus (Sugar Diabetes)
Literally means bland or insipid urine	Literally means honey-sweet urine (back when doctors would sometimes actually taste people's urine to make a diagnosis)
Uncommon	Common
Caused by the lack of the antidiuretic hormone (vasopressin) or the kidney's inability to respond to this hormone	Caused by lack of the hormone insulin
Urination is more frequent and in much greater volumes than the more common sugar diabetes	Urination is less frequent and in much lesser volumes than Diabetes Insipidus
Diagnosed via Water deprivation test/vasopressin test	Diagnosed via Fast blood sugar-24hr. post-prandial test. Glucose tolerance test.