... and what is wrong with wiki answers may i ask...
this answer is not from wiki. so rest asured.
it is from another website (see source)
ps ... it is long.
this is because this is a very tricky and 'slippery slope' topic which needs a lot of words to EXACTLY describe what is meant by what word or term and what is excluded/ not applicable. to be so pedantic with words is good , because people have been prosecuted or set free for assisting based on these very words.
Euthanasia: the intentional killing by act or omission of a dependent human being for his or her alleged benefit. (The key word here is "intentional". If death is not intended, it is not an act of euthanasia)
Voluntary euthanasia: When the person who is killed has requested to be killed.
Non-voluntary: When the person who is killed made no request and gave no consent.
Involuntary euthanasia: When the person who is killed made an expressed wish to the contrary.
Assisted suicide: Someone provides an individual with the information, guidance, and means to take his or her own life with the intention that they will be used for this purpose. When it is a doctor who helps another person to kill themselves it is called "physician assisted suicide."
Euthanasia By Action: Intentionally causing a person's death by performing an action such as by giving a lethal injection.
Euthanasia By Omission: Intentionally causing death by not providing necessary and ordinary (usual and customary) care or food and water.
What Euthanasia is NOT: There is no euthanasia unless the death is intentionally caused by what was done or not done. Thus, some medical actions that are often labeled "passive euthanasia" are no form of euthanasia, since the intention to take life is lacking. These acts include not commencing treatment that would not provide a benefit to the patient, withdrawing treatment that has been shown to be ineffective, too burdensome or is unwanted, and the giving of high doses of pain-killers that may endanger life, when they have been shown to be necessary. All those are part of good medical practice, endorsed by law, when they are properly carried out.