Biochips can perform hundreds or thousands of biochemical reactions simultaneously on a surface no larger than a fingernail. They are used to analyze genes in cells and for applications in biology and medicine. A biochip consists of a microchip, antenna coil, capacitor, and glass capsule implanted under the skin. It communicates with a reader via radio signals. Biochips can identify diseases like sepsis from a blood sample within 20 minutes, faster than other methods. They allow multiple tests to be done at once and have advantages for applications in healthcare, forensics, and tracking of shipments.