The Arduino Uno is perhaps the most well-known and widely used Arduino. The board, based on the ATmega328, provides everything you need to program microcontrollers. Simply connect your computer to the board via a USB cable or use an external power supply or battery, and you're ready to go.

In Revision 3, an ATmega16u2 replaces the ATmega8u2 from the previous version as the USB-to-Serial converter. The ATmega328 controller features 14 digital input/output pins (6 of which can be used in PWM mode), 6 analog inputs, a 16 MHz crystal oscillator, a USB port (Type B), a power jack, an ICSP header, and a reset button.

This version of the Arduino Uno is the DIP version. It differs from the SMD variant by having a larger and more easily replaceable microcontroller in a DIP package. This makes it much simpler to replace a faulty controller or to use a programmed microcontroller in a separate circuit independent of the Arduino board.

Arduino is an open-source physical computing platform that is based on easy-to-use hardware and software. The goal of this platform is to enable artists, designers, hobbyists, and other enthusiasts to create interactive objects. Sensors and microcontrollers are used to make analog inputs available to software applications and/or to control electromechanical devices such as motors, servos, LEDs, or other hardware.