If you die it's game over, the original save file is deleted, and you must start again. You can only save progress in buildings or when you sleep. Your objective is to survive as long as you can while the game simulates a full day/night cycle affecting wildlife, windchill and other dangers.
You can play in Story or Survival mode in one of the six regions: 'Mystery Lake', 'Coastal Highway', 'Pleasant Valley', 'Forlorn Muskeg', 'Desolation Point', and 'Timberwolf Mountain'.
This means taking on not only the harsh environment by wildlife and other environmental dangers. Through exploring, crafting and fighting you must look after your body temperature, caloric intake, hunger, thirst and fatigue. The Long Dark is a thoughtful exploration-survival game where you have crash-landed in the icy Canadian wilderness after a global disaster and must find a way to survive.