Arduino is hardware, based on microcontrollers(ATmega8, ATmega168, ATmega328, ATmega1280, ATmega2560) which can be used for different applications as a prototype computing platform, which can work almost like a microcomputer.
It is a open source Hardware-Software Platform
The Arduino board contains the microcontroller as its processing unit, memory, cache, interfaces, inputs and output pins, and all other interfaces which are required to use it as a processing unit.
Image : Arduino Rev 3
The above is a picture of an Arduino Uno Rev 3 board. This uses Atmel's ATMega328 Microcontroller. This is the first microcontroller which marks the invention of the Arduino Series. Earlier it was Arduino Uno and after slight modifications, they named it as Arduino Uno Rev 3.
This is the Best Arduino to start with and we shall confine our entire discussion up to this Arduino. The code written in the Arduino IDE can be later transferred to any other versions of Arduino, it will work fine.
The Arduino Project started in Interaction Design Institute Ivrea, Italy. It was a project started by the students of the institute under the supervision of Massimo Banzi and Casey Reas.
Later in 2003, they named the Project as Arduino. The first microcontro