A few weeks ago, on October 16, the world celebrated World Anesthesia Day, honoring the discovery that forever changed medicine. Before anesthesia, surgery was… let’s just say a waking nightmare. Doctors relied on alcohol, narcotics, or even a good whack on the head to knock patients out. Thankfully, modern anesthesia means tens of thousands of people every day can undergo surgery without pain… or memory… of the ordeal. Curious how it all works? Find out in this fascinating video from Reactions.