This document provides an introduction to the Arduino microcontroller. It discusses that Arduino allows users to control electronics like LEDs and robots. It then lists some common Arduino boards like the Arduino Uno, and describes the Uno in more detail, noting its 14 digital pins, 6 analog pins, USB connection, and on-board LED. Finally, it provides basic instructions on how to code for Arduino by downloading the IDE, selecting the board type, and gives an example blink project using digitalWrite().