1. Arduino Uno: The Arduino Uno is the most popular Arduino board and is great for beginners. It is a microcontroller board based on the ATmega328P chip.
2. Arduino Mega: The Arduino Mega is a larger board that has more RAM, I/O pins, and processing power than the Arduino Uno. It is great for more complex projects.
3. Arduino Nano: The Arduino Nano is a small board that is great for projects that require a lot of I/O pins in a small form factor.
4. Arduino Pro Mini: The Arduino Pro Mini is a smaller version of the Arduino Uno. It has fewer I/O pins and less processing power, but it is great for projects that don’t require a lot of power.
5. Arduino Due: The Arduino Due is a powerful board that is based on the ARM Cortex-M3 processor. It is great for projects that require a lot of processing power.
6. Arduino Yún: The Arduino Yún is a board that combines the power of the Arduino with the power of the Linux operating system. It is great for projects that require a lot of networking capabilities.