Euthanasia refers to the act of intentionally ending a life to relieve suffering. It is classified as either active or passive, and voluntary, non-voluntary, or involuntary. While legal in some places like the Netherlands and some US states, it remains controversial. Religions generally oppose euthanasia as against the sanctity of life. Proponents argue it relieves pain, while opponents fear a slippery slope and devaluing of human life. Public opinion varies with some supporting legalization with safeguards while others fear abuse or pressure on the terminally ill.