An 
informative new documentary is out about Arduino, “an open-source electronics prototyping platform based on flexible, easy-to-use hardware and software” (source: arduino.cc). You can find all sorts of free software to use with your Arduino board so you can make a lot of interesting devices: robots that crawl, 3-D printers to make other real-world objects, blinking light controllers, and tons of other things. Your imagination is really the limit of what you can do with Arduino.
Arduino comes with inseparable freedoms because Arduino’s environment is built to give you the freedom to explore whatever you want: Arduino software is licensed to share and modify under the GNU General Public License and this software has been ported to run on any operating system, Arduino’s getting-started documentation is licensed under Creative Commons Attribution-ShareAlike 3.0 License so share and alter that to your taste too (so long as you pass on the freedoms you got), and the Arduino Uno board works with any computer that has USB (which is virtually every computer you’ll use). You are empowered to do all sorts of interesting things with Arduino, as participants in the documentary attest to.
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