A person is allowed to defend themselves, or other in their home, or workplace. While deadly force is allowed, it is only to be used when all other options have been exhausted, and the person feels they are in immediate danger.
Castle Laws are laws that address the use of force when defending one's self inside their home, or on their property. Some states expand this to vehicles, and the person's place of work. Castle Laws generally include: the places where this law applies, the requirements fro use of deadly force, if there is a duty to retreat, the amount of force that maybe used in defending one's self or others. These vary widely from state to state.