Death is the irreversible end of life, marked by the cessation of cardiopulmonary (heart and lung) functions and the permanent cessation of all biological functions that sustain life, traditionally the heart, lungs, and brain. Irreversible cessation of all functions of the entire brain, including the brain stem, even if a ventilator keeps the heart beating—a series of events where vital organs shut down, leading to the body's eventual decomposition. However, modern definitions also recognize brain death (irreversible cessation of all brain function) as a legal and medical standard, representing a transition from life to decomposition, viewed variously as a biological process, a spiritual journey, or a natural end to the life cycle.
Many cultures see death as a natural, inevitable part of life and the universe's cycle, contributing to new life. Religions like Islam view it as a passage to another, eternal life, while Judaism emphasizes an afterlife, and Christianity sees it as separation from God due to sin. Explores the biological, psychological, cultural, and social aspects of dying and death. Death signifies the end of an individual organism's existence, defined medically by the irreversible failure of vital systems, but understood through a spectrum of spiritual, cultural, and philosophical lenses.