The Arduino is a "is an open-source electronics platform based on easy-to-use hardware and software."(1) The processor allows us to control a very large variety of motors, lights, and other actuators. It runs on the Arduino computer program and reads Arduino code. Arduino code is a version of C++ programming language used by the processor and is becoming very popular. The Arduino is a new age alternative to the older Basic Stamp processors we used to use. The Arduinos are more efficient, powerful, and adverse.
(1): http://www.arduino.cc/