Arduino is an open-source physical computing platform based on a simple i/o board and a development environment that implements the Processing/Wiring language. Arduino can be used to develop stand-alone interactive objects or can be connected to software on your computer (e.g. Flash, Processing, MaxMSP). The boards can be assembled by hand or purchased preassembled; the open-source IDE can be downloaded for free at http://www.arduino.cc/en/Main/Software
For more information, see the website at: http://www.arduino.cc/ or the forums at: http://www.arduino.cc/forum/
You can also follow Arduino on twitter at: https://twitter.com/arduino or like Arduino on Facebook at: https://www.facebook.com/official.arduino
To report a bug in the software or to request a simple enhancement go to: http://github.com/arduino/Arduino/issues
More complex requests and technical discussion should go on the Arduino Developers mailing list: https://groups.google.com/a/arduino.cc/forum/#!forum/developers
If you're interested in modifying or extending the Arduino software, we strongly suggest discussing your ideas on the Developers mailing list before starting to work on them. That way you can coordinate with the Arduino Team and others, giving your work a higher chance of being integrated into the official release https://groups.google.com/a/arduino.cc/forum/#!forum/developers
Detailed instructions are in reference/Guide_Windows.html and reference/Guide_MacOSX.html. For Linux, see the Arduino playground: http://www.arduino.cc/playground/Learning/Linux
Arduino is an open source project, supported by many.
The Arduino team is composed of Massimo Banzi, David Cuartielles, Tom Igoe, Gianluca Martino, Daniela Antonietti, and David A. Mellis.
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