Remember when you were a kid, running around with your friends, imagining having superpowers and fighting the bad guys? Eventually you outgrew it and are now having a regular human job, but a lot of scientists are driven by their imaginations and are working on technologies to augment ourselves into superhumans.

Human augmentation can aid produce better prosthetics or reduce genetic disorders, and could create a better life for a lot of people – but it also raises the question of where to draw the line: Where does a human stop being human and start becoming a machine?