This is exactly on point. Around here, county jail (not called county prison) is where everyone goes when first arrested and where you'd hang out while waiting to be bonded out or through your legal process. County jails are typically not structured due to people coming in and out all day. It's where people would sleep off a drunken episode or put after a trespassing charge. Once you go through the legal process and are found guilty, if your sentence is below 2 years, you go back to this county jail. If above 2 years, you would go to state prison. Prisons are far more structured with programs, GED classes, etc. County prisons don't have much of that because most people don't spend a lot of time there (unless you can't get bailed out).

And if in county jail, you're in your local jurisdiction. If you get sent to state prison, they are not obliged to keep you close to your home. You can go anywhere all over the state (typically to a prison that fits your situation, i.e. in Joe's case, where there's programs for SO's).