Arduino: Arrival
The Arduino, as described by the Arduino Homepage, is "an open-source electronics prototyping platform based on flexible, easy-to-use hardware and software." What that means to you may differ with your experience, but to me the Arduino is a little chunk of Italian-made circuit board that can make LEDs blink, can tell how bright the ambient light is, can run motors and mechanisms, and otherwise make electronic components do cool stuff.
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