Cryonics is the act of freezing a dead body so that someday it can be revived when future technology can bring them back to life. The chances for success are slim. But is it a bad idea?
Humans have been trying to cheat death for as long as we've existed. The drive to live longer, to survive, seems etched into our DNA. The entire field of medicine exists for that one reason - to extend human life.
Our medical technology has progressed by leaps and bounds over the years and along the way our notions of death has changed as well. We no longer see it as a state, but a process. And some have taken this notion to extremes and believe that you can freeze that process indefinitely so that future medicine can cure you. This is cryonics.
There are a handful of major cryonics companies, including Alcor, the Cryonics Institute, and KrioRus. They have spent years mastering the cryopreservation process that starts as soon as possible after the body is declared dead.
Whether this process will actually work is unknown, but it's a bet cryonicists are willing to take.