Death is the termination of all biological functions that sustain a living organism. Phenomena which commonly bring about death include biological aging (senescence), predation, malnutrition, disease, suicide, homicide, starvation, dehydration, and accidents or trauma resulting in terminal injury. Bodies of living organisms begin to decompose shortly after death. Death has commonly been considered a sad or unpleasant occasion, due to the termination of bonds with or affection for the being that has died, or having fear of death, necrophobia, anxiety, sorrow, grief, emotional pain, depression, sympathy, compassion, solitude, or saudade.
Death is irreversible. In fiction, bringing a dead animal back to life is called resurrection. In recent years, medical doctors have blurred the line considered death, with successful recoveries of humans that have been clinically dead for five minutes or more. Much of the brain damage occurs from oxidative damage as the body recovers, and doctors have become much more adept at managing this through controlled hypothermia and other methods.
Recovery from near death is called a near death experience. Many people who have done so report seeing a bright light and having pleasant feelings. It is unknown if this is a due to a biochemical process in the brain or if it represents the existence of an immortal spirit entering another realm such as heaven. This topic was explored in an episode of Magnum, P.I..