Any AVR microcontroller based board which follows the standard Arduino schematic and is flashed with the Arduino bootloader can be called an arduino board. There is no other tool available which helps in easy prototyping like the Arduino does. The Arduino board has all the required circuitary to get the built-in AVR microcontroller running. When it comes to programming the Arduino board anyone who have basic knowledge of c programming can quickly get started with the Arduino IDE. It is very simple to understand and has built-in functions for almost every simple or complex task. All the Arduino boards are flashed with the arduino boot-loader which enables them to be connected and programmed with the Arduino IDE.The Arduino can act as a stand-alone system which can take inputs, process the inputs and generate the output. The arduino can communicate with the other devices using its digital I/O, serial port, I2C port, SPI port etc