Jody Culkin has published a comic explaining how to use an arduino. It's a good read for people who have considered giving arduino a go but have been nervous of the complexity of developing for hardware. 

The comic gives a really good explanation of the basic features and as a bonus explains electricity in a way that I can almost remember Ohm's law. 

Go have an educating read

Read the comic

The arduino is an open-source prototyping platform for electronics. 

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