Electronic skin is a material that mimics human skin and can measure vital signs like heart rate and brain waves. It is made of flexible silicon sensors laminated onto skin like a temporary tattoo. The sensors form a spider web-like circuit that detects pressure, temperature and other bodily functions and transmits the signals to monitoring devices. Electronic skin has applications in healthcare for wound monitoring and in robotics for making machines more human-like. While promising, challenges remain in reducing the cost and enabling reuse of electronic skin technologies.