Cryonics is a technique to preserve legally dead individuals at low temperatures in liquid nitrogen with the goal of future revival when medical technologies allow for repair of damage from aging, disease, or the freezing process. The document discusses the cryonics process, which involves replacing a patient's blood with cryoprotectants to prevent ice crystal formation before cooling the body to liquid nitrogen temperatures. It also discusses companies that offer cryonics services and the costs associated with whole body or neuropreservation. The ultimate goal of cryonics is to give individuals the opportunity to be revived when medical advances can cure what caused their death.