If you've ever had a major surgery then you have probably had the strange experience of being anesthetized. 

When you are under anesthesia you can't feel pain, form memories or move, but you are not really asleep either. 

Humans have been using different forms of anesthesia for several centuries, but in the last 150 years we have made a lot of progress in the field of anesthesiology. 

In this informative animated Ted-Ed video, Steven Zheng discusses what anesthesia is, how it works and the science behind it. 

Tell us about your experiences with anesthesia or just let us know what you thought of the video in the comments section below!