Euthanasia is to signify an easy death through the mitigation of pain rather than a death hastened by a physician through the administration of poison. It is where someone intentionally kills a person whose life is felt not to be worth living. It does not include stopping or starting a medically useless treatment, relieving pain when the intention is to kill the pain but not the patient, or refusal of medical treatment by a competent patient. Euthanasia is categorized in different ways, which include voluntary, non-voluntary, or involuntary. Voluntary euthanasia is legal in some countries. Non-voluntary euthanasia  is illegal in all countries. Involuntary euthanasia is also illegal in all countries and is usually considered murder.