In this paper, we analyze the working principle of an arduino. These days many people try to use the arduino because it makes things easier due to the simplified version of C++ and the already made Arduino microcontroller(atmega328 microcontroller [1]) that you can programme, erase and reprogramme at any given time. In this paper we will discuss the hardware components used in the arduino board, the software used to programme it (Arduino board) with the guide on how to write and construct your own projects, and a couple of examples of an arduino project, This will give you the overall view of an arduino uno, that after reading this paper you will get the basic concept and use of an arduino uno.