A woman waves her hand, and her car roars to life. She touches her unadorned ear to take a call in the car as she drives to a cryotherapy parlor. She is a biohacker. What other technologies might humans use to optimize themselves? In Biohackers, readers will learn about three types of biohacking, from body implants to DNA manipulation. They will learn the stories of the scientists and engineers who have experimented with hacking their own bodies, pushing the envelope of what makes humans human.