What's the difference between a mental institution, a psych ward and a hospital for the criminally insane?

"A mental institution would be where people that are mentally ill would go if they cannot take care of themselves and have no one else that can take care of them. A psych ward is a ward in a hospital for people that are having temporary problems. Like any other ward in the hospital you will stay there until you are well enough to take care of yourself and return to society. A hospital for the criminally insane is actually a prison hospital for people that have committed crimes and because of their mental illnesses they are a danger to themselves and others and cannot be housed in a regular prison. They will receive treatment and medication while they are there." On Quora Answered by Kammy XXXXXXX, Survivor of 60 years of life with Bipolar 2