"If you have a friend or relative who has been asking “what’s an Arduino?” You can point them here. They’ll get an overview of what it is and what’s possible with it." from Source: http://blog.makezine.com/arduino/
"Arduino is a single-board microcontroller designed to make the process of using electronics in multidisciplinary projects more accessible. The hardware consists of a simple open source hardware board designed around an 8-bit Atmel AVR microcontroller, though a new model has been designed around a 32-bit Atmel ARM. The software consists of a standard programming language compiler and a boot loader that executes on the microcontroller.
Arduino boards can be purchased pre-assembled or do-it-yourself kits. Hardware design information is available for those who would like to assemble an Arduino by hand. There are sixteen official Arduinos that have been commercially produced to date. Numerous hardware variations of the Arduino are being sold by third parties." from Source: http://en.wikipedia.org/wiki/Arduino