"ARDUINO IS AN OPEN-SOURCE ELECTRONICS PROTOTYPING PLATFORM
BASED ON FLEXIBLE, EASY-TO-USE HARDWARE AND SOFTWARE.
IT'S INTENDED FOR ARTISTS, DESIGNERS, HOBBYISTS
AND ANYONE INTERESTED IN CREATING
INTERACTIVE OBJECTS OR ENVIRONMENTS."
An Arduino is a microcontroller
roughly comparable to the on-board computer
on the Apollo 11 lander.
It is useful for connecting to
low-level electronic components,
which allows you to "hack" the real world.
void setup () { ... }
void loop () { ... }