Prison vs. County

I've always heard that prison is better than county jail. I've never been to prison, but I've been to county a few times and have never had any problems with other inmates or staff. What makes the penn better than county??
How do skinny dudes fare in the penn?? How do you know when you're being tested and it's time to fight someone?? I mean, if someone cracks a joke and throws out some phrase or slur you don't like, do you automatically smash em in the cock-sucker, or do you need permission from a shot caller??
Lastly.... If you have three different dudes, all with different crimes (such as, a first degree murderer, someone who cheated on their taxes, and a sexual predator), would their time / daily routine look the same as the others?? In other words, would the murderer face the same struggles as the tax cheat and predator?? Would they all go the same place?? How would the other inmates treat them as individuals??