A Living Will is also called a Health Care Directive or Advance Care Directive.
Advance health care directive - Wikipedia, the free encyclopedia
The purpose of a Living Will is quite different from that of a "regular" will, or "last will and testament", which basically allocates your assets after you die. A Living Will tells your family, friends and healthcare providers what you want done with
you, while you are alive, in the event that you are in a coma or otherwise unable to communicate your wishes. For example, if you were comatose or in a permanent vegetative state, or demented, would you want CPR done? Dialysis? Would you want to be put on a ventilator? Generally speaking, the more specifically you write this document, the more helpful it is to your loved ones and healthcare providers. A directive that says "do everything" is less helpful than one that says "I am willing to be put on a ventilator provided that it is a short term treatment". Once you die, a Living Will becomes irrelevant and then your Last Will and Testament kicks in.
Living Wills are legally binding documents in many jurisdictions. One of the most useful benefits is to avoid the "daughter from California" syndrome, in which Mother has a stroke and can't speak, son believes we should make her comfortable, and daughter (who has been out of town for 10 years and never calls at Christmas) rushes in and wants to have Mother kept on life support and transferred to Mexico for untested treatment costing $50K. Yes, this does happen!
I have a Living Will. My closest relatives and friends have copies, as does my doctor. If my doctor knows I have one, and contravenes my wishes, I or my health care proxy could complain or even take hiim/her to court. Some hospitals have policies that ensure that adults being admitted are routinely asked whether they have a living will or advance care directive.
A Health Care Proxy is someone whom you appoint to manage your affairs while you are unable to do so for any reason. The details of the Proxy's scope vary by jurisdiction.
I'm sure Rich and Martha can 'splain this better than I can....
So which kind of a will do you think you need?