Arduino is a single-board microcontroller. It is intended to make the application of interactive objects or environments more accessible. The hardware consists of an open-source hardware board designed around an 8-bit Atmel AVR microcontroller, or a 32-bit Atmel ARM. Here, we are listing out some of the best and very useful Arduino project ideas which are collected from different resources and are very interesting to implement them. Recommended read: Arduino Starter Kits.