What is the difference between state jail and prison?

To me it just seems the names are different. My husband is doing prison time in a state jail facility. Some things are considered state jail offenses and some are prison offenses. But, they can all serve it together. Not much help, sorry about that.

a state jail felony is a sentence of no more than 2 yrs.

prison is any amount of time

I can't be quoted on this, but in my own personal research this is what I get from it so far. My fiancee is in a state jail which consists of state jail and prison.

state jails usually consist of non violent offenders sentenced to 2 years or less but state jails are also used as intake/transfer facilities. doesn't make any kind of sense does it?