If you're a zombie, half of your humanity is controlled by fungus and you have to eat human meat, have to stay in cold places, and to not get wet from water, jus to survive and live. If you're a human, you have to survive as a human. Just don't get bitten by walkers, be sick, starve and dehydrated, so you can survive. The world was in chaos, there were no evidence to what started the zombie apocalypse. Everyone is on their own now for survival. The world is in chaos so don't die.