This document discusses using JavaScript for embedded programming on microcontrollers. It introduces Espruino, which allows programming microcontrollers using JavaScript. Espruino provides inexpensive hardware with peripherals and libraries, making it suitable for hobbyists and prototyping. In contrast to Arduino, Espruino includes a debugger. The document demonstrates examples of using Espruino to read temperature and humidity sensors and expose sensor data over Bluetooth Low Energy. It encourages exploring Espruino and related projects like Tessel and Neonious for embedded JavaScript development.